Tägliche Übungen - Mathematik   Klasse 11-I GK

1.) Zusammenfassen von Termen

1.1) Addition von Termen

nach Termen mit gemeinsamer Variablenkonstellation ordnen

zusammenfassen durch Ausklammern der gemeinsamen Variablenkonstellation     

  1. 3x² + 7x² - 14x² + 35x²  = x² · (3 + 7 – 14 + 35) = x² · 31  = 31x²
  2. 33a – 7b – 10a + 8b – 17a + 22b                                                                                  = 6a + 23b
  3. 13x + 5xy – 4z – 6x + 14xy + 16z – 7z                                                                        = 7x + 19xy + 5z
  4. 18x² + 14u – 13x² - 2x + 2u + 4x – u                                                                          = 15u + 5x² + 2x
  5. 12a² + 4a³ + 17a³ - 3a² - 5x                                                                                         = 21a³ + 9a² - 5x
  6. 25ax – 13x + 12x²                                                                                                           = 25ax + 12x²  – 13x
  7. 14uvw + 5uv –22w + 35uw –13uvw + 21w –35uw + 25u² - 12v² - 24u² + 13v² = u² + v² - w + 5uv + uvw
  1. 17y + 13x² - 14ax² - 7x² + 20ax² + 15bx –13xy + 10bx – 4xy                               = 6x² + 25bx + 6ax²
  2. 2a² - 2b² - 3a²b + 5b² + 10a² - 6a² + 6a²b                                                                = 6a² + 3b² + 3a²b
  3. 0,8x² + 0,2a² - 1,2a – 1,7x² - 0,3a + 0,7a² + 1,9x² + a² + 2a                                = -0,5a + 1,9a² + x

1.2) Multiplikation von Termen

Koeffizienten und Variablen gesondert multiplizieren

bei Variablen gegebenenfalls Potenzschreibweise (und –gesetze) nutzen    

  1. 4·7x                                                                                       = 28x
  2. 3x·20y                                                                                   = 60xy
  3. 14u·2v                                                                                   = 28uv
  4. 4a·7c·2x                                                                                = 56acx
  5. 3s·4t·5s                                                                                 = 60s²t
  6. 7s·2s·3t                                                                                 = 42s²t
  7. 2x·3y·4x·2y  = 2·3·4·2 · x·x·y·y  =  48x²y²
  8. 3x·y·5x·3y                                                                             = 45x²y²
  9. 5x·3y·4xy                                                                              = 60x²y²
  10. 3xy·7xz                                                                                  = 21x²yz
  11. 3xz·4y·3yz                                                                             = 36xy²z²
  12. 2x²·4y·2y·3x                                                                          = 48x³y²
  13. 3a²·4ab·2ab²                                                                         = 24a4
  14. 2a·3x²·4ax·5xz·2a³                                                              = 240a5x4z

1.3) Vermischte Aufgaben

erst Multiplikationsterme vereinfachen, dann zusammenfassen  

  1. 3a·2b – 4ab + 3x·5y – 2x·3y                                                           = 2ab + 9xy
  2. 4x·3y + 2u·2v + 2u·4v – 3y·2x                                                        = 12uv + 6xy
  3. 2y·3z – 2x²·4z + 3xyz + 2x·5xz + 4z·5y                                       = 3xyz + 2x²z + 26yz
  4. 3x·4y² + 10x·3a – 5a·2ab – 2y·2xy + 7ax - x·2a + 15a²·2b      = 20a²b + 35ax + 8xy²
  5. 3u²·7 – 12a²·2b + 8x·5y·3z – 7x·4y – 2y² - 7u·3u – 15yz·8x + y·3y + 14y·2x= y² - 24a²b
  1. 3x²·2x² - x·5x³ + 2x·5x·2x·10x – 2x³·3x + 10x4                        = 205x4
  2. 17xyz – 5x·3y + y·20x – 2yz·3x + z·5xy + 5y·10x                       = 55xy + 16xyz
  3. 3a²·4ab + 10a·2ab – 6b·2a³ - 3a·2a³b² + a²b·6ab + 3a²b·4a  = 20a²b + 24a³b + 6a³b² - 6a4b

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2.) Rechnen mit Termen

2.1) Addition und Subtraktion

gleiche Vorzeichen:  Beträge addieren, Vorzeichen bleibt

ungleiche Vorzeichen: Beträge subtrahieren, Vorzeichen von Zahl mit größerem Betrag

Additionszeichen zwischen Termen kann wegfallen

  1. (-5) + (-4)                                                                     = -9
  2. (-3,5) + (-7) + (-5) + (-3)                                          = -18,5
  3. –7,4 + 5  =  (-7,4) + (+5)  =  -(7,4 – 5)  =  -2,4
  4. 3 – 11                                                                              = -8
  5. –5 + 3 – 11 – 10 + 3 – 5                                               =-25
  6. 5,2 – 7,4 + 3,2 – 4,3 – 5,3 + 3,4                                 = -5,2
  7. –1,5x + 0,9x – 2,5x + 1,1x – 3x + 5                           = -5x + 5
  8. 3y – 3x + 3y + 5x – 8y – 10x                                       = -8x – 2y
  9. 4s + 6t – 6s – 4t + 2t – 2s                                            = -4s + 4t
  10. 3,4p – 0,4x + 0,4p – 5,4x + 4,6p + (-9,4p)               = -p – 5,8x
  11. 12xy – 12x – 12y – 18xy + 6x + 4y                             = -6x – 6xy – 8y
  12. 1,4s – 0,4t + 1,4st – 0,9s – 0,1t – 0,6st                      = 0,5s + 0,8st – 0,5t
  13. –1,5t + 3,7s + (-1,7s) – 1,5t + 5t – 2s                        = 2t
  14. 3t – 4x + 7t – 10t – 14t + 2x – 10t + 2x                      = -24t 
  15. 1,2a – 0,2b – 1,8a – 1,2b + 0,2a + 0,8c – 0,8a          = -1,2a – 1,4b + 0,8c

2.2) Multiplikation und Division

Gesamtvorzeichen Minus bei ungerader Anzahl von Minuszeichen

Punktrechnung (RO zweiter Stufe) geht vor Strichrechnung (RO erster Stufe)    

  1. 3,2·5                                                                                                                                                     = 16
  2. (-3,2)·(+5)                                                                                                                                          = -16
  3. (-3,2)·(-5)                                                                                                                                           = 16
  4. 4,2:(-1,2)                                                                                                                                             = -7/2   = -3,5
  5. (-4,2):(-2)                                                                                                                                           = 2,1
  6. 1,7·(-2)                                                                                                                                                = -3,4
  7. (-4,8)·(-1)                                                                                                                                           = 4,8
  8. (-3)·(-4)·(-2)·(+4)                                                                                                                            = -96
  9. 7x·(-2y)·(-0,5x)                                                                                                                                 = 7x²y
  10. (-5y)·3y·(- 0,2 x)·(-2)                                                                                                            = -6xy²
  11. –3x +(-4x)·(5y) –(6x·3y) +(-5x)·(-2) = -3x +(-20xy) –18xy +(+10x) = -3x +10x–20xy –18xy = 7x –38xy
  1. 7s·3(-4s)·(-6) + (4t)·(-2) – 7t                                                                                                     = -3s – 15t
  2. –(-3x)·(2y)·(-4z) + (-2z)·(-x)·(-12y) + (-0,5y)·(24xz)·(-2) – (-8xyz)·(-6)·(-0,5)              = 0xyz = 0
  1. (-3x)·(-3x²)·(2x)·(-2y) – (7x³)·(-6y) + (14y)·(-3x³) – (12x4)·(3y)            = 0x³y - 72x4y = -72x4y
  2. (-2a)·(-2a) + (0,5 a)·( - 0,5 )·(8a) – ( b)·(- b) + ( 0,5 b²)·(-                                     = 2a² -

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3.) Rechnen mit Klammern

3.1) Auflösen von Klammern

Plusklammer: Pluszeichen und Klammer fallen weg; alle Terme in der Klammer behalten ihr Vorzeichen bei

Minusklammer: Minuszeichen und Klammer fallen weg; von allen Terme in der Klammer ist das Entgegen- gesetzte zu bilden

Mehrfachklammern: schrittweise von innen nach außen auflösen  

  1. 7 + (+ x – 12 )                                            =  7 + x 12                                                  =  x – 5
  2. 2s (+ 4s – 4 )                                           =  2s 4s + 4                                                =  -2s + 4
  3. +(+ 3x – 2y ) ( +4x – 5 – 5y )               =  3x 2y 4x + 5 + 5y                              =  -x +3y + 5
  4. 24k² -(+40k + 16k² - 4) –(+24k + 6)     =  24k² - 40k – 16k² + 4 – 24k – 6            =  8k² - 64k –2
  5. 2x–[+5x² -(+5x – 2)]+(-3x + 2) + 5x² =  2x – [ 5x² - 5x + 2 ] – 3x +2+5x²                                                                       =  2x – 5x² + 5x – 2 – 3x + 2 + 5x²          =  4x
  6. 4t – [+3s – (+2t – 3s ) + 6 ] – 6               =  4t – [ 3s – 2t + 3s + 6 ] – 6                                                                       =  4t – 3s + 2t – 3s – 6 – 6                          =  -6s + 6t – 12
  7. –(+4a–3)–[(+3x²+x)–(+4x+4x²)–(-3x–x²)] =  -4a + 3 – [ 3x² + x – 4x – 4x² + 3x +x²]                                                                          =  -4a +3 – 3x² -x + 4x +4x² -3x - x²     =  -4a + 3
  8. –(-3x+2x²+5)–(+4x²+2x+5) +(+6x²-10) = 3x –2x² -5 –4x² -2x –5 +6x² - 10    =  x - 20

3.2) Distributivgesetz

jeder Summand in der Klammer ist mit dem (vorzeichenbehafteten) Faktor außerhalb der Klammer zu multiplizieren

  1.  5·( 3x – 2 )                                                                                                               =  15x – 10

  2.  7·( 4s – 3t ) - 8·( 2s + 5t )                =  28s – 21t – 16s – 40t                            =  12s – 61t

  3.  –4t·( 2s – 3 ) + 2s·( 4t – 3 )             =  -8st + 12t + 8st – 6s                             =  12t – 6s

  4.  ( 5k – 4 )·5 - 2·( 8k – 10 )                 =  25k – 20 – 16k + 20                              =  9k

  5.   2x·( 2 – 2x + 5y ) – 2y·( 5x – 2 )     =  4x – 4x² + 10xy – 10xy + 4y              =  -4x² + 4x + 4y

  6.   –3(4a–3b–3b²+2a²)–4(-3a–1,5a² =  -12a +9b +9b² -6a² +12a +6a²         =  9b² + 9b

  7.  4x( x – y) –[ 3x( x +y) –2x( x –y)] =  4x² - 4xy – [ 3x² + 3xy – 2x² + 2xy]                                                               =  4x² - 4xy – 3x² - 3xy + 2x² - 2xy      =  3x² - 9xy

  8.  5(-2a+b)–2[(3a–5b)·4+(12–9a)·a]= -10a + 5b – 2[ 12a – 20b + 12a – 9a²]                                                             =-10a +5b – 4a +40b –24a +18a²         =  18a² - 58a + 45b

  9.             4[ 4s(t–s)(s+4t)·3] – 7s(s+8)     =  4[ 4st – 4s² - 3s – 12t ] – 7s² - 56s                                                                                =  16st –16s² -12s –48t –7s² -56s         =  -23s² - 68s + 16st – 48t

  10. 10.  (-2)[(-3t)(2a – b)(-4a)(10 – 2t)] – (-6)(3a + 7t) = (-2)[-6at + 3bt + 40a – 8at] + 18a +42t                                                            = 12at – 6bt – 80a + 16at + 18a + 42t   = -62a + 28at – 6bt + 42t

3.3) Multiplikation von Summen

  jeder Summand der einen Klammer ist mit jedem Summanden der anderen Klammer zu multiplizieren

  beachten Sie die Struktur der Terme (Summe, Differenz, Produkt, Quotient, Potenz)   

  1. ( 7t + 8e )( x + 1 )                                                                                  = 7tx + 7t + 8ex + 8e  

  2. ( 5t² - 8t )( 2t³ + 4 )                                                                               = 10t5 – 16t4 + 20t² - 32t 

  3. ( 4x² + 2,5y )( -x – 2y )                                                                          = -4x³ - 8x²y – 2,5xy – 5y² 

  4. (2x–3y–2)(4–2x+2y)=8x –4x² +4xy –12y +6xy –6y² -8 +4x –4    = -4x² + 12x + 10xy – 16y – 6y² - 8y 

  5. ( x – 2)( -3x – 5 – y) = -3x² -5x –xy +6x +10 +2y                            = -3x² + x – xy + 2y + 10

  6. (2x+y)(x–y)–[(x+3)(2x–4y)+3(4y–2x)]=2x²-2xy+xy–y²-[2x²-4xy+6x-12y+12y–6x] = + 3xy – y² 

  7. ( a + b )( 2a – 1 )·b       = (2a² - a + 2ab – b)·b                                  = 2a²b – ab + 2ab² - b² 

  8. (x – 1)(x² + 2x – 1) – (x² - 2x + 1)(x + 2) = x³ +2x² -x –x² -2x +1 = x³ + x² - 3x + 1 

  9. a(3a – b + 2ab – 1) – (a – b)(3a – b) = 3a² -ab +2a²b –a [3a² -3ab –ab +b²] =  2a2b + 3ab – a – b² 

  10. (-3x)(2x+3y)-(2x–3y)(3+4x–2y)=-6x²-9xy–[6x+8x²-4xy–9y–12xy+6y²]= -14x² - 6x + 7xy + 9y – 6y

3.4) Ausklammern (Faktorisieren)

gemeinsame Faktoren aller Summanden vor die neugebildete Klammer schreiben 

die Restglieder in der Klammer erhält man durch Division der Ausgangssummanden mit dem auszuklam- mernden Term   

  1. 4xy + 2x – 6xy          = 2·2·x·y + 2·x2·3·x·y                                             =  2x · ( 2y + 1 – 3y )  = 2x·(-y +1)

  2. a + b - c         = · 2a + · 5b - · c                                                 =  · (2a + 5b – c)

  3. 42abc² - 30ab²c – 28a²bc = 2·3·7·a·b·c·c – 2·3·5·a·b·b·c2·2·7·a·a·b·c     =  2abc· ( 21c – 15b – 14a)

  4. a³ - 2a² + 4a                          =  a·a·a – 2·a·a + 2·2·a                                        =  a · ( a² - 2a + 4 )  

  5. –a – b                        =  -1·a – 1·b                                                                         =  -1 · ( a + b )

  6. a( 5x – 2y ) – b( 5x – 2y )                                                                                    =  ( a – b ) · ( 5x – 2y )

  7. x( 3a – b ) + y(-3a + b ) + 3az – bz  =  ( 3a – b ) - y·( 3a – b ) + z·( 3a – b ) =  (3a – b) · (x – y + z)  

  8. 3at – 5bt + 3as – 5bs  = 3a ·( t + s ) – 5b ·( t + s )                                           =  ( 3a – 5b ) · ( t + s )

  9. 3bx–7ax+6b²-14ab–12ab+28a²=3·b·x–7·a·x+2·3·b·b–2·7·a·b-2·2·3·a·b+2·2·7·a·a=(3b-7a)·(x+2b-4a)                                                                                                                                                                                                                    oder =  3b · (x + 2b) +a · (-7x - 26b + 28a)                                                                                                     oder =  x ·(3b – 7a) + 2 ·(3b² - 13ab +14a²)                                                                                                     oder  =  b ·(3x + 6b – 26a) + 7a ·(-x +4a) 

  10. sx²y–tx²y+3ps–3pt–4as+4at=s·x·x·y–t·x·x·y+3·p·s–3·p·t–4·a·s+4·a·t=x²y·(s–t)+3p·(s–t)–4a·(s–t)                                                                                                                                  =  (s – t) · (x²y + 3p – 4a)

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4.) Binomische Formeln

benutzen Sie die Formeln aus dem Tafelwerk     

verwandeln Sie Binome in Summen  bzw. Summen zurück in Binome

  1. ( s + t )²                                             =  s² + 2st + t²   

  2. ( 12s + 4t )²                                       =  144s² + 96st + 16t²

  3. ( 5x + 6y )²                                        =  25x² + 60xy + 36y²

  4. ( 9a + 6b )²                                        =  81a² + 108ab + 36b²

  5. 4s² + 12st + 9t²                                 =  (2s + 3t)²

  6. 9x² + 4y² + 12xy                               =  (3x + 2y)²

  7. t² + 2t + 1                                           =  (t + 1)²

  8. 400n² + 9m² + 120mn                      =  (20n + 3m)²

  9. ( 1,2x + 5y )²                                     =  1,44x² + 12xy + 25y²

  10. ( s – t )²                                              =  s² - 2st + t²

  11. ( 8n – 0,5m )²                                    =  64n² - 8mn + 0,25m²

  12. k² - 24kl + 144l²                                =  (k – 12l)²

  13. 16s² + 25t² - 40st                             =  (4s - 5t)²

  14. x² -x + 0,25                                       =  (x - 0,5

  15. x² - 2x + 1                                          =  (x – 1)²

  16. 25d² + 36c² - 60cd                            =  (5d – 6c)²

  17. 9x² + 64y² - 24xy                              = kein vollständiges Quadrat  (-24xy ist kein doppeltes Produkt!)

  18. x4 + 100 – 20x²                                  =  (x² - 10)²

  19. 4x² + 0,25· y² - xy                            =  (2x - 0,5 y)²

  20. ( 2s + 5t )( 2s – 5t )                           =  4s² - 25t²

  21. ( x + 12s )( x – 12s )                        =  x² - 144s2

  22. ( 16x – 11y )( 16x + 11y )               =  256x² - 121y²

  23. 9y² - 25                                                =  (3y + 5)·(3y – 5)

  24. 169 – 144x²                                         =  (13 + 12x) ·(13 – 12x)

  25. 196a² - 225b²                                     =  (14a + 15b)·(14a – 15b)

  26. 256p² - 16pq + 0,25                      =  (16p - 0,5 q)²

  27. x² -                                        =  ( x + y)· ( x - y)

  28. 36a² - 4ab +                                  =  (6a – 2b)²

  29.  + 2x + 100x²                              =  ( + 10x)²

  30. ( x² - 6x )²                                     =  x4 – x³ + 36x²

  31. x4 – y4                                                   =  (x² + y²)·(x² - y²)

  32. 4x4 – 25x²                                            =  (2x² + 5x)·(2x² - 5x)

  33. a² -                                     =  ( a + b)· ( a + b)

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5.) Faktorisieren von Termen

  1. 3as + 5at – 6bs – 10bt                                 =  a·(3s + 5t) – 2b·(3s + 5t)                      =  (a – 2b) ·(3s + 5t)
  2. 15a² + 30ab + 15b²                                     =  15 · (a² + 2ab + b²)                               =  15 · (a + b)²
  3. 8g² - 8h²                                                        =  8 · (g² - h²)                                             =  8 · (g + h) · (g – h)
  4. 18x + 12ux + 2u²x – 27y – 18uy – 3u²y   =  2x · (9+6u+u²)-3y·(9+6u+u²)             =  (2x – 3y) · (u + 3)²
  5. 18s³ - 60s²t + 50st²                                     =  2s · (9s² - 30st + 25t²)                          =  2s · (3s – 5t)²
  6. 6a²xz+12a²vx+6a²yz+12a²vy = 6a²z·(x+y)+12a²v·(x+y) =(6a²z+12a²v)·(x+y)=  6a²·(z+2v)·(x+y)
  7. 5a²-5b²+4a²+8ab+4b²=5·(a²-b²)+4·(a²+2ab+b²)=5·(a+b)·(a–b)+4·(a+b)²      =  (a+b)·[5·(a-b)+4(a+b)]
  8. 4x²-2xy+12x²+3y²-12xy=2x·(2x–y)+3·(4x²-4xy+y²)=2x·(2x–y)+3·(2x–y)²       =  (2x–y)·[2x+3·(2x–y)]
  9. 4x5 – 24x4 + 36x³                                         =  4x³ · (x² - 6x + 9)                                  =  4x³ · (x – 3)²
  10. 3x³ - 48x                                                        =  3x · (x² - 16)                                           =  3x · (x + 4) · (x – 4)

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6.) Bruchterme

6.1) Grundmenge und Definitionsbereich

Aufgabe: Bestimmen Sie den Definitionsbereich folgender Bruchterme bzgl. des Grundbereichs der rationalen Zahlen!

beachten Sie: ein Bruch ist nicht definiert , wenn der Nenner Null und der Zähler ungleich Null ist

sollten beide Terme für eine Zahl Null werden, kann der Bruch gekürzt werden

  1.                                       NR: 3 – x    0                     DB = { x  R |  x ≠ 3}
  2.                                       NR: a + 4    0                     DB = { a  R |  a ≠ -4}
  3.                               NR: 2x    0                          DB = { x  R |  x ≠ 0}
  4.                                  NR: 3 – 8a    0                    DB = { a  R |  a ≠ 3/8}
  5.                NR: a – 7 ≠ 0 und a ≠ 0      DB = { a  R |  a ≠ 0 und a ≠ 7}
  6.                                    NR: b² + 4    0                   DB = { b  R }
  7.            Kürzen von x möglich                            DB = { x  R}
  8.    NR: 12x–20 ≠ 0     DB = { x  R | x ≠ 5/3 }
  9.               NR: x – 1    0                      DB = { x  R |  x ≠ 1}
  10.      NR: 3x + 5    0                   DB = { x  R |  x ≠ - 5/3}

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6.2) Erweitern von Bruchtermen

Aufgabe: Erweitern Sie den Bruchterm mit dem angegebenen Erweiterungsfaktor!

beachten Sie: Erweitern eines Bruches bedeutet , Zähler und Nenner mit dem gleichen Term multiplizieren

nutzen Sie danach ihre Fertigkeiten beim Multiplizieren von Summen

  1.            erweitern mit  2x       
  2.            erweitern mit  ( 2a – 4 )        
  3.          erweitern mit  ( 3xy – 2 )        
  4.          erweitern mit  ( a – b )        
  5.         erweitern mit  ( a + b )        

    Aufgabe: Erweitern Sie den Bruchterm so dass der angegebene Nenner entsteht!

    ermitteln Sie zunächst den Erweiterungsterm durch Division des neuen Nenners durch den alten Nenner
    erweitern Sie danach den Bruch wie in den vorhergehenden Aufgaben
  6.         auf den Nenner:  10b – 15            
  7.            auf den Nenner:  10ab² - 15ab       
  8.          auf den Nenner:  12x²z + 18xz²       
  9.          auf den Nenner:  a² - b²        

    Aufgabe: Machen Sie die jeweils gegebenen Bruchterme gleichnamig!

    ermitteln Sie zunächst den Hauptnenner beider Brüche als kleinstes gemeinsames Vielfache (kgV) beider Nenner

    erweitern Sie dann beide Brüche auf diesen Hauptnenner

  10.            auf den Nenner:  9a² + 6ab + b²        
  11. ;             
  12.              ;
  13.             
  14.             
  15.             

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6.3) Kürzen von Bruchtermen

ermitteln Sie zunächst den größten gemeinsamen Teiler (ggT) von Zähler und Nenner (gegebenenfalls durch geschicktes Ausklammern)

kürzen sie dann gemeinsame Faktoren in Zähler und Nenner

  1. =  
  2. =
  3. nicht kürzbar, weil Zähler nicht in Produkt zerlegbar
  4. nicht kürzbar, weil der Nenner nicht in Produkt zerlegbar

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6.4) Vereinfachung von Bruchtermen, Polynomdivision

Aufgabe: Vereinfachen Sie den Bruchterm durch Zerlegen von Zähler und Nenner in

                  Faktoren und anschließendes Kürzen!

Verfahren der Polynomdivision siehe Arbeitblatt  

 

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7.) Rechnen mit Bruchtermen

7.1) Addition gleichnamiger Bruchterme

Zähler addieren, Nenner beibehalten

  1. + = = x2
  2. - =
  3. - - =
  4. - - = =
  5. - - = =

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7.2) Addition ungleichnamiger Bruchterme

ermitteln Sie zunächst das kleinste gemeinsame Vielfache (kgV) der beiden Nenner (Hauptnenner)

erweitern sie dann beide Brüche auf den gemeinsamen Hauptnenner

addieren sie nun die gleichnamigen Brüche

  1. + =
  2. -  =
  3. - -  =
  4. - =
  5. + = 
  6. +  = 
  7. +  = 
  8. -  +  = =
  9. -  = 
  10. -  =  =
  11. -  +  =  =  = 
  12. +  =  = 
  13. -  + =  =    = = 
  14. -  +  -  =  =  =  = 

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7.3) Multiplikation von Bruchtermen  

multiplizieren Sie zunächst Zähler mit Zähler und Nenner mit Nenner

kürzen sie dann gemeinsame Faktoren in Zähler und Nenner und vereinfachen Sie den Bruch  

  1. ·20xy  =  = 16uy
  2. =  
  3. =  
  4. =  
  5. =  
  6. =  
  7. = ap²r
  8.  · ( 20x – 25y )  = xy  
  9. =
  10. =  
  11. =  
  12. · ( a + 2 )  
  13.  

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7.4) Division von Bruchtermen 

ersetzen Sie zunächst die Division mit dem 2.Bruch (Divisor) durch eine Multiplikation mit dessen Reziproken 

gehen sie nun vor wie beim Multiplizieren zweier Brüche  

  1. =  
  2. : 2x  =  
  3. 4x :   =  
  4. =  
  5. =  
  6. =
  7. =
  8. =  
  9. =  
  10. =  
  11. =  
  12. =  
  13. =
  14. =

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8.) Lineare Gleichungen und Bruchgleichungen

8.1) Grundbereich, Definitionsbereich und Lösungsmenge

 

Bestimmen Sie den Definitionsbereich und die Lösungsmenge der Gleichung jeweils für den Grundbereich der rationalen Zahlen Q, der ganzen Zahlen Z und der natürlichen Zahlen N! 

           

  1.   3 + x  =  2                    DB = R                                         x = -1           LQ = {-1}        LZ = {-1}          LN = Ø

  2.   7 – x  =  12 – 2x          DB = R                                         x = 5             LQ = {5}          LZ = {5}           LN = {5}         

  3.   =  2                          DB = {xR|x0}                       x = 4             LQ = {4}          LZ = {4}           LN = {4}  

  4. =                      DB = {xR|x≠2 und x≠0,25}  x = 1            LQ = {1}          LZ = {1}           LN = {1}

  5.   =  1                      DB = {xR|x≠0,75}                x = -1           LQ = {-1}        LZ = {-1}         LN = Ø

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8.2) Bestimmung der Lösungsmenge einfacher Gleichungen

 

1.      5x + 7  =  3x + 25   /-3x                                                                                                2.           2x – 17  =  17 – 3x   /+3x

 2x + 7  =  25   /-7                                                              5x –17  =  17   /+17

        2x  =  18   /:2                                                                     5x   =  34   /:5

        x = 9                                                                                        x = 6,8 

   

3.      2x – 9( 3x + 1 )  =  3( x – 7 ) + 5( x + 2 )         4.   3( 5x – 2 ) + 7( 4 – x )  =  4(5 + x ) – 11( 2x – 7 ) + 4x

       2x – 27x – 9  =  3x – 21 + 5x + 10                              15x – 6 + 28 – 7x   =  20 + 4x – 22x + 77 + 4x

              -25x – 9  =  8x – 11   /+25x                                                    8x + 22  =  -14x  + 97   /+14x

                        -9   =  33x – 11   /+11                                                  22x + 22  =   97   /-22

                          2   =  33x   /:33                                                                    22x  =  75   /:22

                         x   =   ( 0,0606)                                                                 x  =     (3,40909)

 

5.      13( 2x – 6 ) – 5( 3 + x )  =  4( 23 – 4x ) + 2( x – 7 ) + 7( x – 13 )

                    26x – 78 – 15 – 5x  =  92 – 16x + 2x – 14 + 7x – 91

                                     21x – 93  =  -7x – 13   /+7x

                                     28x – 93  =  -13   /+93

                                             28x  =  80   /:28 

                                                 x  =    (2,857142)  

6.      1,5( x – 4 ) - 0,5· ( 7 – 8x )  =  0,75· ( 16x – 7 ) – 8( 12x + 0,5 ) + 74,5x

                          1,5x – 6 – 3,5 + 4x  =  12x – 5,25 - 96x – 4 + 74,5x

                                         5,5x – 9,5  =  -9,5x – 9,25   /+9,5x

                                         15x – 9,5   =  -9,25   /+9,5

                                                    15x  =  0,25   /:15

                                                         x  =      (0,0166)  

7.              ( x – 7 )² - 15( x + 7 )  =  ( x – 2 )( x + 2 ) – 5( 3 + 4x ) + 8x

         x² - 14x + 49 –15x – 105  =  x² - 4 – 15 – 20x + 8x  

                              x² - 29x – 56  =  x² - 12x – 19   /-x²

                                   - 29x – 56  =   -12x – 19   /+29x + 19

                                              - 37  =  17x

                                                   x  =      (-2,176470588)  

8.               3x( x – 5 ) + 2( 3 – 2x )²  =  2x( 9 + 2x ) + ( 5 – 3x )( 2 – 5x ) – 8x²

           3x² - 15x + 2( 9 – 12x + 4x² ) = 18x + 4x² + 10 – 25x – 6x + 15x² - 8x²

                3x² - 15x + 18 – 24x + 8x²  =  18x + 4x² + 10 – 25x – 6x + 15x² - 8x²

                                   11x² - 39x + 18  =  11x² - 13x + 10   /-11x²

                                             - 39x + 18  =  - 13x + 10   /+39x -10

                                                         + 8  =  26x   /:26

                                                             x  =     (0,307692)  

9.      ( x – 5 )( 5 – x ) – 4x( 2 – x )  =  ( 7x – 2 )( x + 5 ) – 2x( 2x + 3 )

            5x – x² - 25 + 5x – 8x + 4x²  =  7x² + 35x – 2x – 10 – 4x² - 6x

                                     3x² + 2x – 25  =  3x² + 27x – 10   /-3x²

                                                2x – 25  =  27x – 10   /-2x + 10

                                                       -15  =  25x   /:25

                                                           x  =    (-0,6)  

10.                                                       5x( x – 2 )² + 0,2· ( 4x – 2 )( 8 – 5x ) + 5x  =  2( 6x + 4 )( 7 – 2x ) – x( 7 – 5x² )

           5x( x² - 4x + 4 ) + 0,2·( 32x – 20x² - 16 + 10x ) + 5x  =  2( 42x – 12x² + 28 – 8x ) – 7x + 5x³

                          5x³ - 20x² + 20x + 6,4x – 4x² - 3,2 + 2x + 5x  =  84x – 24x² + 56 – 16x – 7x + 5x³

                                                               5x³ - 24x² + 33,4x – 3,2  =  5x³ - 24x² + 61x + 56   /-5x³

                                                                       -24x² + 33,4x – 3,2  =  -24x² + 61x + 56   /+24x²

                                                                                      33,4x – 3,2  =  61x + 56   /-33,4x - 56

                                                                                                -59,2  =  27,6x   /:27,6

                                                                                                                                  x  =     (-2,14493)

    11.                     4 -   =  3 -   /·20

                4·20 -   = 3·20 -

                    80 - 4·( 7 – 3x )  =  60 - 2·( 3 – 7x ) + 10·( x + 1 )

                        80 – 28 + 12x  =  60 – 6 + 14x + 10x + 10

                                12x + 52  =  24x + 64   /-24x

                               -12x + 52  =  64   /-52

                                        -12x  =  12   /:( -12)

                                              x  =  -1                              Probe:   2  =  2  w.A.

    12.                    - 4  =    1 -    /·12

               - 12·4  = 12·1 -

                 4·( 4x – 1 ) – 48  =  12 - 2·( x – 4 ) + 3·( 3x + 5 ) - 3·17

                       16x – 4 – 48  =  12 – 2x + 8 + 9x + 15 – 51

                

                              16x – 52  =  7x – 16   /-7x

                                9x – 52  =  -16   /+52

                                        9x  = 36   /:9

                                           x  =  4                             Probe:   1  =  1  w.A.

    13.                                    + 6  =     /·30

            ·( x + 3 ) + 30·6  = 

               10·( 7x – 2 ) - 24·( x + 3 ) + 180  =  45·( x + 2 )

                           70x – 20 – 24x - 72 + 180  =  45x + 90

                                                         46x – 88  =  45x + 90   /-45x

                                                             x + 88  =  90   /-88

                                                                      x  =  2          Probe:   6  =  6  w.A.

    14.                             / ·120  

                 

          8·( 2x – 3 ) - 6·( 4x – 9 )  =  4·( 8x – 27 ) – 5·( 16x – 81 ) - 3·9

                  16x – 24 – 24x + 54  =  32x –108 – 80x + 405 – 27

                                      -8x + 30  =  -48x + 270   /+48x

                                      40x + 30  =  270   /-30

                                               40x  =  240   /:40

                                                   x  =  6                      Probe:      w.A.

8.3) Bruchgleichungen

·        Ermitteln Sie die Lösungsmenge folgender Bruchgleichungen, in dem Sie:

-         den Definitionsbereich bestimmen

-         mit dem Hauptnenner beide Seiten multiplizieren

-         die bruchfreie Gleichung lösen

-         überprüfen, ob die Lösung im Definitionsbereich liegt

             -         eine Probe in der Ausgangsgleichung machen

 

1.      =  - - 33 /·4x                          DB = { x  R |  x ≠ 0} }

     5 = -28 – 132x /+28

   33 = - 132x

     x = -1/4 = -0,25          Probe: -5 = -5 w.A.          L = {-1/4}  

 

2.          =    /·(2-x)(3-x)                     DB = { x  R |  x ≠ 2 und x ≠ 3 }

3·(3 – x) = 2·(2 – x)

    9 – 3x = 4 – 2x /+3x   /-4

            5 = x                    Probe: -1 = -1 w.A.          L = {5}

 

3.       +   =  /·(2-3x)(x+3)   DB = { x  R |  x ≠ 2/3 und x ≠ -3 }

x + 3 + 2·(2 – 3x) = 3·(2 – 3x)

                     7 – 5x = 6 – 9x /+9x – 7

                           4x = -1

                             x = -1/4 = -0,25       Probe: 12/11 = 12/11 w.A.         L = {-1/4}

 

4.        =   + 3 /·2(2-x)                    DB = { x  R |  x ≠ 2}

             7 = 10 + 3·(4 – 2x)

             7 = 22 – 6x /+6x – 7

           6x = 15

             x = 5/2 = 2,5                        Probe: -7 = -7 w.A.          L = {5/2}

 

5.                       +     =  2 /·(2+x)(3-x)               DB = { x  R |  x ≠ -2 und x ≠ 3 }   

2x·(3 – x) + 3·(2 + x) = 2·(2 + x)(3 – x)

        6x – 2x² + 6 + 3x = 2·(6 + x – x²)

               -2x² + 9x + 6 = -2x² + 2x + 12 /+2x²

                           9x + 6 = 2x + 12 /-2x – 6

                                  7x = 6

                                    x = 6/7           Probe: 2 = 2 w.A.       L = {6/7}

 

6.            =   /·6(3x+2)                    DB = { x  R |  x ≠ -2/3 }

3·(7x – 4) = 2·(5x – 6)

   21x – 12 = 10x – 12 /-10x + 12

            11x = 0

                x = 0                  Probe: -1 = -1 w.A.          L = {0}

 

7.                           -   =   - /·2(3+x)(2+x)       DB = { x  R |  x ≠ -3 und x ≠ -2 }

8·(2 + x) – 14·(3 + x) = 3·(3 + x) – 5(2 + x)

      16 + 8x – 42 – 14x = 9 + 3x – 10 – 5x

                        -6x – 26 = -2x – 1 /+6x + 1

                                 -25 = 4x

                                     x = -25/4 = -6,25        Probe: 92/221 = 92/221 w.A.         L = {-25/4}

 

 

8.                       =  +  /·(x+7)(x-7)           DB = { x  R |  x ≠ 7 und x ≠ -7 }

(3 + x)(x + 7) = x² + 9·(x – 7)

 x² + 10x + 21 = x² + 9x – 63 /-x²

          10x + 21 = 9x – 63 /-9x – 21

                        x = -84          Probe: 81/91 = 81/91 w.A.          L = {-84}

 

 

9.                 +   =  /·6(5+x)(5-x)       DB = { x  R |  x ≠ 5 und x ≠ -5 }

3x·(5 + x) – 2·(5 – x)  =  6·(0,5x² + x)

   15x + 3x² - 10 + 2x  =  3x² + 6x

           3x² + 17x – 10  =  3x² + 6x /-3x²

                      17x – 10  =  6x /-6x + 10

                                11x = 10  

                                    x = 10/11         Probe: 32/585 = 32/585 w.A.         L = {10/11}

 

 

10.                                   -   =   -  /·2(1-x)(1+x)          DB = { x  R |  x ≠ 1 und x ≠ -1 }

10·(1 + x) – 6x·(1 – x)  =  6x² - 3·(1 – x)

     10 + 10x – 6x + 6x²  =  6x² - 3 + 3x

                6x² + 4x + 10  =  6x² + 3x – 3 /-6x²

                           4x + 10  =  3x – 3 /-3x – 10

                                       x = -13                        Probe: -81/28 = -81/28 w.A.              L = {-13}

 

 

11.              -   =    /·2(5+x)(2-x)  DB = { x  R |  x ≠ 2 und x ≠ -5 }

8x·(2 – x) – 8x·(5 + x)  =  16x·(2 – x)

  16x – 8x² - 40x – 8x²  = 32x – 16x²

                    -16x² - 24x  =  -16x² + 32x /-8x²

                                -24x  =  32x /+24x

                                       0 = 56x /:56

                                       x = 0              Probe: 0 = 0 w.A.       L = {0}

 

12.              +   =   +  /·3x(x-5)(x+2)     DB = { x  R |  x ≠ 5 und x ≠ -2 und x ≠ 0 }

9x·(x + 2) + 6x·(x – 5) = 12x·(x – 5) + 3·(x² - 3x – 10)

 9x² + 18x + 6x² - 30x  =  12x² - 60x + 3x² - 9x - 30

                      15x² -12x  =  15x² - 69x – 30 /-15x²

                                -12x  =  -69x – 30 /+69x

                                 57x  =  -30

                                      x  =  -10/19       Probe: 57/70 = 57/70 w.A.     L = {-10/19}

13.     +   =   + /·2x(x-3)       DB = { x  R |  x ≠ 0 und x ≠ 3 }

2x + 6·(x – 3)  =  6·(x – 3) + x

   2x + 6x – 18  =  6x – 18 + x

            8x – 18  =  7x – 18 /-7x + 18

                        x = 0           gehört nicht zum DB      Probe: nicht möglich       L = Ø

  

14.   -   =  /·7(3+2x)²   DB = { x  R |  x ≠ -3/2 }

              7·(3 + 2x) – 7x  =  3,5·(3 + 2x)

                 21 + 14x – 7x  =  10,5 + 7x

                           21 + 7x  = 10, 5 + 7x /-7x – 10,5

                                 10,5  =  0  Widerspruch       Probe: nicht möglich              L = Ø

    

15.                  +   =   - /·2x(3+x)(3-x)    DB = { x  R |  x ≠ 3 und x ≠ -3 und x ≠ 0 }

4x·(3 – x) + 2x·(3 + x)  =  -4x² – 2·(9 – x²)

   12x – 4x² + 6x + 2x²  =  -4x² – 18 + 2x²

                     -2x² + 18x  =  -2x² - 18 /+2x²

                                   18x = -18

                                        x = -1             Probe: 5/4 = 5/4 w.A.         L = {-1}

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9.) Ungleichungen und Bruchungleichungen

9.1) Bestimmung der Lösungsmenge einfacher Ungleichungen  

-          beachten Sie die Unterschiede bei den Äquivalenzumformungen zwischen Gleichungen und Ungleichungen und geben Sie die Lösungsmenge im Bereich der reellen Zahlen an!

1.  3 + 2x    -7 – 3x /+3x – 3                        2.  4 + 7x  >  3x – 16 /-3x – 4

             5x  -10 /:5                                                        4x > -20 /:4

               x  -2          L = {x R| x  -2 }                     x > -5            L = {x R| x > -5 }

 

 

3.  13x – 5  10x + 23 /-10x + 5                   4.  25x – 12  <  20x + 28 /-20x + 12

               3x 28 /:3                                                           5x < 30 /:5

                 x         L = {x R| x 28/3 }                     x < 6           L = {x R| x < 6 }

 

 

5.  3x + 5  <  5x – 7 /-5x - 5                             6.  x – 3  <  2x + 5 /-2x + 3

            -2x < -12 /:(-2)                                                 -x < 8 /·(-1)

                x > 6             L = {x R| x > 6 }                     x > -8                L = {x R| x > -8 }

 

 

7.  2x – 0,2  <  4x + 3 /-4x + 0,2                      8.  2x + 2,5   6x – 1,5 /-2x + 1,5

              -2x < 3,2 /:(-2)                                                       4  4x /:4

                  x > -1,6      L = {x R| x > -1,6 }                      x          L = {x R| x  1 }

 

 

9.  0,5x – 7  -2x – 8 /+2x + 7                      10.  –1,5( x – 3 ) + x   2x -

              x  -1 /·                                               -1,5x + 4,5 + x  2x -

                 x   -       L = {x R| x -2/5 }                            -0,5x  2x -  /-2x

                                                                                     

    - x - /·(- )

      -4      -3      -2      -1       0       1        2       3                     x               L = {x R| x 3/20 }

Die Lösungsmenge einer Ungleichung ist in der Regel eine unendlich große Zahlenmenge, die durch einen bestimmten Bereich auf der Zahlengerade veranschaulicht werden kann.

 

9.2) Bruchungleichungen  

Bestimmen Sie die Lösungsmenge der Bruchungleichungen, in dem Sie:

-          den Definitionsbereich der Ungleichung ermitteln

-          die Ungleichung mit dem Hauptnenner durchmultiplizieren

-          dabei eine Fallunterscheidung vornehmen für den Fall, dass der Hauptnenner größer(gleich) Null bzw. dass der Hauptnenner kleiner als Null ist

-          die entstandenen Teilungleichungen lösen und mit der Fallbedingung vergleichen

-          die Gesamtlösungsmenge aus den Lösungsmengen der beiden Teilungleichungen zusammensetzen und graphisch veranschaulichen

-          mit geeigneten ganzen Zahlen aus der Lösungsmenge eine Probe machen

1.                                                >  0 /·x         DB = { x R| x ≠ 0}

                                  x < 0                               x > 0

                       x  + 2  <  0 /-2                           x  +  2  >  0 /-2

                               x  <  -2                                         x  >  -2

                       L1 = { x R| x < -2}                 L2 = {x R| x > 0}             L = {x R| x < -2 und x > 0}  

               

                        -3             -2            -1             0              1              2              3

  2.                                                >  0 /·x      DB = { x R| x ≠ 0}

                                  x < 0                           x > 0

                       3  -  x  <  0 /+x                          3  -  x  >  0 /+x

                              x  >  3                                         x  <  3

            L1 = Ø                                L2 = {x R| 0 < x < 3}        L = {x R| 0 < x < 3}

  3.                                              0 /·x          DB = { x R| x ≠ 0}

                                  x < 0                           x > 0

                       x  -  5  0 /+5                     x  -  5  0 /+5

                               x  5                                    x   5

            L1 = Ø                          L2 = {x R| 0 < x  5}           L = {x R| 0 < x  5}

 

4.                                              0 /·3x       DB = { x R| x ≠ 0}

                 x < 0                           x > 0

                       1  - 2x    0 /+2x             1  - 2x  0 /+2x

                              2x    1 /:2                       2x  1

                                x   0,5                              x  0,5

               L1 = Ø                        L2 = {x R| 0 < x  0,5}        L = {x R| 0 < x 0,5}

 

5.                                                >  0           DB = { x R| x ≠ 1}

                                                     >  0

                                                             3  >  0          L = {x R}  

6.                                              0 /·(x+2)           DB = { x R| x ≠ -2}

                                  x < -2                          x > -2

                       x  -  1  0 /+1                    x  -  1  0 /+1

                               x  1                                   x  1

              L1 = Ø                       L2 = {x R| -2 < x 1}                L = {x R| -2 < x 1}

7.                                              0 /·(x-4)          DB = { x R| x ≠ 4}

                                  x < 4                           x > 4

                       2x  +  5  0 /-5                       2x + 5  0 /-5

                               2x  -5 /:2                             2x  -5 /:2

                                 x  -2,5                                    x -2,5

      L1 = { x R| x  -2,5}             L2 = {x R| x > 4}                L = {x R| x  -2,5 und x > 4}

8.                                                < 0                DB = { x R| x ≠ -0,5}

                                  x < -0,5                       x > -0,5

                       2x  -  7  >  0 /+7                 2x  -  7  <  0 /+7

                              2x  >  7 /:2                           2x  <  7 /:2

                                x  >  3,5                                x  < 3,5

              L1 = Ø                          L2 = {x R| -0,5 < x < 3,5}            L = {x R| -0,5 < x < 3,5}

9.                                              >  0 /·(5x+2)          DB = {x R| x ≠ -0,4}

                                  x < -0,4                       x > -0,4

                       5  -  3x  <  0 /+3x                5  -  3x  >  0 /+3x

                               3x  >  5 /:3                           3x  <  5 /:3

                                 x  >                                     x  < 

               L1 = Ø                          L2 = {x R| -0,4 < x <  }            L = {x R| -0,4 < x <  }

 

10.                                              < 2 /·(3-x)         DB = { x R| x ≠ 3}

                                  x < 3                                           x > 3

                       4x  +  5 <  2·(3-x) /+2x - 5        4x  +  5  >  6 – 2x /+2x - 5

                               6x  <  1 /:6                                     6x  >  1 /:6

                                 x  <                                               x  > 

      L1 = { x R| x  < }                      L2 = { x R| x > 3}             L = {x R| x < und x > 3}

 11.                                              > 3 /·(2x+5)              DB = { x R| x ≠ }

                                  x < -2,5                                   x > -2,5

                       5  +  x  <  3·(2x+5) /-6x - 5        5  +  x  >  6x + 15 /-6x - 5

                            -5x  <  10 /:(-5)                            -5x  >  10 /:(-5)

                                x  > -2                                              x < -2

              L1 = Ø                                     L2 = {x R| -2,5 < x < -2}        L = {x R|  -2,5 < x < -2}

 12.                                              5 /·(1-x)                DB = { x R| x ≠ 1}

                                  x < 1                                   x > 1

                       x  -  7  5·(1-x) /+x            x  -  7  5 – 5x /+5x + 7

                             6x  12 /:6                           6x  12 /:6

                               x  2                                      x  2

    L1 = { x R| x < 1}               L2 = {x R| x   2}                    L = {x R| x < 1 und x   2}

13.                                              1 /·(3x-5)            DB = { x R| x ≠ }

                                  x < 5/3                        x > 5/3

                       2x  -  7  3x - 5 /-3x + 7         2x  -  7  3x - 5 /-3x + 7

                                -x  2                                         -x  2

                                  x  -2                                         x  -2

       L1 = { x R| -2 x < 5/3}                L2 = Ø                                L = {x R| -2  x < 5/3}

14.                                               - < 0 /·(x²+x)       DB = { x R| x ≠ 0 und x ≠ -1}

                                  x < -1                        -1 < x < 0                        x > 0

                       2 + 2x  -  x < 0 /-2       2 + 2x  -  x  >  0 /-2       2  +  2x – x  <  0 /-2

                                       x  < -2                             x  >  -2                              x  <  -2

     L1 = { x R| x < -2}     L2 = {x R| -1 < x < 0}               L3 = Ø    L = {x R| x < -2 und -1 < x < 0}

15.                                               + >  0               DB = { x R| x ≠ -2 und x ≠ 3 }

                                  x < -2                    -2 < x < 3                         x > 3

                       2(x-3) + 3(x+2) > 0    2x – 6 + 3x + 6 < 0        5x  >  0 /:5

                                                 x  > 0                           x  < 0           x  >  0

                         L1 = Ø  L2 = {x R| -2 < x < 0}  L3 = {x R| x > 3}    L = {x R| -2 < x < 0 und x > 3}  

 

16.                             - 0 /·(x+1)(2x+6)              DB = { x R| x ≠ -1 und x ≠ -3 }

                                  x < -3                    -3 < x < -1                        x > -1

                       2x+6 - 5(x+1) 0       2x + 6 - 5x - 5 0          -3x + 1 0 /+3x

                                            3x 1                           3x  1                 3x  1

                                              x                              x                     x   

     L1 = { x R| x <-3}               L2 = Ø             L3={xR|-1<x }  L = {x R| x < -3 und -1 < x  }

17.                          + > 0 /·(3x+5)(2x-7)             DB = { x R| x ≠   und x ≠ }

                               x < -5/3                        -5/3 < x < 3,5                        x > 3,5

               -2(2x-7) + 4(3x+5) > 0    -4x + 14 + 12x + 20 < 0       8x +34 >  0 /-34

                              8x  >  -34                               8x  <  -34                  8x  >  -34 /:8

                                x  >  -4,25                              x  <  -4,25                 x  >  -4,25  

       L1 = {x R| -4,25 < x < -5/3}          L2 = Ø                  L3={xR|x>3,5} L={xR|-4,25<x<-5/3 und x>3,5}

18.                             - < 0 /·(x-5)(x+3)                   DB = { x R| x ≠ -3 und x ≠ 5 }

                                  x < -3                          -3 < x < 5                               x > 5

                       2x(x+3) - 2x(x-5) < 0    2x² + 6x - 2x² + 10x > 0         16x  <  0 /:16

                                                   x  <  0                                     x  >  0             x  <  0

         L1 = {x R| x < -3}              L2 = {x R| 0 < x < 5}      L3 = Ø    L = {x R| x < -3 und 0 < x < 5}

19.                          + 3 /·(x-5)(x+1)                   DB = { x R| x ≠ -1 und x ≠ 5 }

                                  x < -1                                      -1 < x < 5                               x > 5

           x(x+1)+2x(x-5) 3(x²-4x-5)  x²+x+2x²-10x 3x²-12x-15  -9x -12x-15 /+12x

                                   3x  -15                                    3x  -15                   3x -15

                                     x  -5                                        x  -5                       x  -5

L1 = {x R| -5  x < -1}                         L2 = Ø             L3={x R|x>5} L = {x R|-5 x<-1 und x>5}

20.                      +   >   /·2(x+1)(x-2)           DB = { x R| x ≠ -1 und x ≠ 2 }

                                  x < -1                                       -1 < x < 2                              x > 2

           2x(x-2)+2x(x-2)>(2x+1)(2x+2)  2x²–4x+2x²-4x<4x²+6x+2   -8x  >  6x + 2 /-6x

                                -14x >  2                                          -14x <  2                -14x >  2 /:(-14)

                                     x < -1/7                                           x  >  -1/7              x  <  -1/7

L1 = {x R| x < -1}                  L2 = {x R| -1/7 < x < 2}            L3 = Ø    L = {x R|x<-1 und -1/7<x<2}

        home                                                            zurück                                                            top

10.) Absolutbetrag, Gleichungen und Ungleichungen

10.1) Der Absolutbetrag 

-          bestimmen Sie – falls möglich – den Betrag oder geben Sie unter Nutzung einer Fallunterscheidung den vereinfachten Term ohne Betragstriche an!

1.      | - 13,5 |  = 13,5

2.      | x – 3 |  =  x – 3  falls x  3         | x – 3 |  =  -x + 3  = 3 – x  falls x < 3

3.      | x + 4 |  = x + 4  falls x  -4        | x + 4 |  = -x - 4  falls x < -4

4.      | 6 – x |  = 6 – x  falls x  6          | 6 – x |  = -6 + x  = x – 6  falls x > 6

5.      | (-2)· 4 |  = | -8 |  =  8

6.      | - x² |  =   für alle x R , weil –x² in jedem Fall negativ, höchstens Null ist

7.        =

8.        =  falls x > 0                         = - falls x < 0                    = nicht definiert für x = 0

9.      | 5x |  = 5x falls x  0                   | 5x |  = -5x falls x < 0

10.  | -3x |  = 3x  falls x                | -3x |  = -3x  falls x < 0

11.    =  falls x -3            =  falls x <-3

12.    =   falls –1 x<2      =  falls x<-1 bzw. falls x>2        für x = 2  nicht definiert

 

10.2) Gleichungen mit  Absolutbeträgen 

Lösen Sie die Betragsgleichungen in dem Sie:

-          wenn nötig den Definitionsbereich einschränken

-          mittels Betragsdefinition eine Fallunterscheidung vornehmen und die Teilgleichungen lösen

-          die Lösungsmenge aus den Teillösungen zusammensetzen und eine Probe machen

 

1.                                                    | x |  =  5

                                        x < 0                            x  0

                                  -x = 5                                      x = 5

                                   x = -5              L = { -5; 5}    

          

2.                                                    | x – 1 |  = 5

                                        x < 1                            x  1

                           -(x - 1) = 5                                      x - 1 = 5 /+1

                           -x + 1  = 5 /-1                                             x  = 6

                                  -x = 4              

x  = -4             L = { -4; 6}     5 Einheiten                         5 Einheiten

 

                                           
                                                    -4      -3      -2      -1       0       1       2        3       4       5        6       7 

                     Lösung sind die zwei Zahlen, die auf der Zahlengerade von der Zahl 1 den Abstand 5 haben

3.                                              | x – 1 | + 1  =  5 /-1

                                                         | x – 1 |  =  4

                                        x < 1                            x  1

                           -x + 1  = 4 /-1                     x - 1 = 4 /+1

                                   -x = 3                                x  = 5

         x = -3              L = { -3; 5} 

 

 

4.                                              | 4x + 1 |  =  3

                                        x < -1/4                        x  -1/4

                           -4x - 1  = 3 /+1                   4x + 1 = 3 /-1

                                  -4x = 4                                 4x  = 2

           x = -1                                  x = 0,5                L = { -1; 0,5} 

  

5.                                              | 4 – 5x |  =  7

                                        x < 0,8                         x  0,8

                           4 – 5x  = 7 /-4                   -4 + 5x = 7 /+4

                                 -5x = 3                               5x  = 11

                                     x = -3/5                            x = 11/5              L = { -0,6; 2,2}  

     6.                                                =  4 /·(2-x)          DB = { x R| x ≠ 2 }

                                              | x + 5 |  =  8 – 4x

                                        x < -5                               x  -5

                           -x - 5  = 8 – 4x /+4x + 5          x + 5 = 8 – 4x /+4x - 5

                                 3x = 13                                     5x  = 3                                   

                                  x = 13/3 (Scheinlösung)         x = 3/5                L = { 0,6 }  

7.                                                =  -1 /·|5-x|         DB = { x R| x ≠ 5 }

                                                    4x - 5  =  - | 5 – x |

                                        x  5                               x > 5

                           4x - 5  = -5 + x /-x + 5          4x - 5 = 5 – x /+x + 5

                                 3x = 0                                     5x  = 10                                   

                                   x = 0                                        x = 2 (Scheinlösung)       L = { 0 }   

8.                                                =  0 /·(x-1,5)     DB = { x R| x ≠ 1,5 }

                                                | 2x – 3 |  =  0

                                        x < 1,5                         x  1,5

                           -2x + 3  = 0 /+2x              2x - 3 = 0 /+3

                                       3 = 2x                           2x  = 3                                  

                                      x = 1,5  DB                  x = 1,5  DB                      L = Ø   

9.                                                        =  2                     DB = { x R| x ≠ 2 }

                                                            = 2 /·|x-2|

                                                     | x – 1 |  =  2· | x – 2 |

                             x < 1                                 1  x < 2                         x  2

               -x + 1  = -2x + 4 /+2x-1      x - 1 = -2x + 4 /+2x+1       x – 1 = 2x – 4 /-2x + 1

                      3x = 3                                 3x  = 5                                     -x  =  -3                        

                        x = 1 (Scheinlösung)         x = 5/3                                  x  =  3           L = {5/3 ; 3}   

10.                                                     =  3 /·|4+x|          DB = { x R| x ≠ -4 }

                                                    | 20 – 2x |  =  3· | 4 + x |

                             x < -4                                    -4  x < 10                              x  10

               20 – 2x  = -12 – 3x /+3x-20      20 – 2x = 12 + 3x /-3x-20   -20 + 2x = 12 + 3x /-3x + 20

                           x = -32                                    -5x  = -8                                       -x  =  32                        

                     L = {-32; 8/5 }                                x = 8/5                                      x  = -32 (Widerspruch)

 

11.                                              | x + 3 | + 2  =  | x – 7 |

                             x < -3                                -3  x < 7                                x  7

               -x – 3 + 2 = -x + 7 /+x+1      x + 3 + 2 = -x + 7 /+x-5       x + 3 + 2 = x – 7 /-x + 5

                              0 = 8 (Widerspruch)           2x  = 2                                       0  =  -2 (Widerspruch)

                                                                                x = 1                                                L = { 1 }   

12.                                              | x + 2 | - 4  = | x – 3 |

                             x < -2                                -2  x < 3                        x  3

               -x – 2 - 4 = -x + 3 /+x+6      x + 2 - 4 = -x + 3 /+x+2      x + 2 - 4 = x – 3 /-x + 2

                             0 = 9 (Widerspruch)         2x  = 5                                   0  =-1 (Widerspruch) 

                                                                             x = 2,5                                 L = { 2,5 }   

13.                                              | x | + | x – 1 |  =  7

                             x < 0                                 0  x < 1                                x  1

               -x – x + 1 = 7 /-1                       x - x + 1 = 7 /-1                       x + x - 1 = 7 /+1

                          -2x = 6                                         0  = 6   (Widerspruch)           2x  =                           

                             x = -3                                    L = { -3 ; 4 }                                    x = 4 

14.                                              3| x | + | 4x – 2 |  =  5

                             x < 0                                 0  x < 0,5                             x  0,5

               -3x – 4x + 2 = 5 /-2                   3x - 4x + 2 = 5 /-2          3x + 4x - 2 = 5 /+2

                              -7x = 3                                         -x  = 3                               7x  =                           

                                 x = -3/7                                      x = -3 (Scheinlösung)     x = 1        L = { -3/7 ;1 }  

 

15.                                              | x + 5 | + | x – 4 |  =  -3

                             x < -5                            -5  x < 4                                   x  4

               -x – 5 – x + 4 = -3 /+1        x + 5 - x + 4 = -3 /+9                       x + 5 + x - 4 = -3 /-1

                                -2x = -2                                   0  = 9 (Widerspruch)                      2x  =  -4

                                              x = 1 (Scheinlösung)            L = Ø                                                  x = -2 (Scheinlösung)

 

10.3) Ungleichungen mit  Absolutbeträgen 

Lösen Sie die Betragsungleichungen in dem Sie:

-          wenn nötig den Definitionsbereich einschränken

-          mittels Betragsdefinition eine Fallunterscheidung vornehmen und die Teilungleichungen lösen

-          die Lösungsmenge aus den Teillösungen zusammensetzen und mit geeigneten ganzen Zahlen aus der Lösungsmenge eine Probe machen  

1.                                              | x | 2

                                        x < 0                            x  0

                                   -x 2 /·(-1)                         x 2

                                    x -2                                   L2 = { x  R; x 2 }                                   

                        L1 = { x  R; x  -2 }                        L = { x  R; x -2 und x 2 }

 

2.                                              | x | 1

                                        x < 0                            x  0

                                   -x 1 /·(-1)                         x 1

                                     x -1                                   L2 = { x  R; x 1 }                                   

                        L1 = { x  R; x -1 }                        L = { x  R; -1 x 1 }

 

3.                                              | x – 4 |  <  2

                                        x < 4                            x  4

                                   -x + 4 < 2 /-4                       x – 4 < 2 /+4

                                          -x < -2                                   x < 6

                                            x > 2                              L2 = { x  R; x < 6 }                                   

                        L1 = { x  R; x > 2 }                        L = { x  R; 2 < x < 6 }                                 

                                                    

                  0          1           2           3          4           5          6          7           8                                                        

        Zur Lösungsmenge gehören alle Zahlen, die von der Zahl 4 einen kleineren Abstand als 2 haben.  

4.                                                      | x + 4 |  <  2

                                                x < -4                           x  -4

                                   -x - 4 < 2 /+4                       x + 4 < 2 /-4

                                         -x < 6 /·(-1)                          x < -2

                                           x > -6                            L2 = { x  R; x < -2 }                                   

                                L1 = { x  R; x > -6 }             L = { x  R; -6 < x < -2 }

 

5.                                                      | x – 4 |   2

                                                x < 4                            x  4

                                   -x + 4 2 /-4                      x – 4  2 /+4

                                          -x -2/·(-1)                       x  6

                                           x  2                          L2 = { x  R; x  6 }                                  

                                L1 = { x  R; x > 2 }              L = { x  R; x 2 und x 6  }

 

6.                                                      | 2x – 7 | 2

                                                x < 3,5                         x  3,5

                                   -2x + 7  2 /-7                   2x – 7  2 /+7

                                          -2x  -5 /:(-2)                   2x  9 /:2

                                              x  2,5                    L2 = { x  R; x  4,5 }                                   

                                L1 = { x  R; x  2,5}             L = { x  R; 2,5 x 4,5 }  

7.                                              | x + 2 | + 1 | x – 2 |

                             x < -2                                -2 x < 2                   x 2

              -x - 2 + 1 -x + 2 /+x+1    x + 2 + 1 -x + 2 /+x-3         x + 2 + 1 x - 2 /-x-3

                            0  3 w.A.                        2   x -1 /:2                                   0 -5 (Widerspruch)

                            x < -2                                     x -0,5                                     L3 = Ø              

                L1 = { x  R; x < -2}            L2 = {x  R; -2 x -0,5 }   L = { x  R; 2,5 x 4,5 } 

 

8.                                              | 2x – 5 | | x + 1 | + 2

                             x < -1                                -1 x < 2,5                           x 2,5

              -2x + 5 -x – 1 + 2 /+x-5  -2x + 5 x + 1 + 2 /-x-5         2x - 5 x + 1 + 2 /-x+5

                       -x -4 /·(-1)                     - 3x  -2 /:(-3)                           x  8

                         x 4                                       x  2/3                           L3 = {x  R; 2,5 x 8 }              

                        L1 = Ø                          L2 = {x  R; 2/3 x < 2,5 }   L = { x  R; 2/3 x 8 } 

 

9.                                              | x | + 1 | x – 5 |

                             x < 0                                 0 x < 5                    x 5

              -x + 1 -x + 5 /+x-1          x + 1 -x + 5 /+x-1         x + 1 x - 5 /+x-1

                      0 4 /·(-1)                       2x 4 /:2                              0 -6

                        L1 = Ø                                x 2                                   L3 = Ø                                                

                                                            L2 = {x  R; 2  x < 5 }   L = { x  R; 2  x < 5 } 

10.                                                <  4 /·2x            DB = { x  R ; x ≠ 0}

x < 0                           x  0

| 3x – 5 | > 8x                           | 3x – 5 | < 8x

                                                                             0  x < 5/3                      x  5/3

                    -3x + 5 > 8x /+3x                    -3x + 5 < 8x /+3x              3x - 5 < 8x /-3x

                               5 > 11x / :11                            5 < 11x /:11                    -5 < 5x

                               x < 5/11                                    x > 5/11                            x > -1              

                    L1 = {x  R; x < 0 }        L2 = {x  R; 5/11 < x < 5/3 }      L3 = {x  R; x 5/3 }

L = { x  R; x < 0  und 5/11  x < ∞ } 

11.                                                >  5 /·x              DB = { x  R ; x ≠ 0}

                x < 0                                                  x 0

                    | 4x + 2 | < 5x                                             | 4x + 2 | > 5x

                    ∞ < x < -0,5           -0,5  x < 0

              -4x - 2 < 5x /+4x                 4x + 2 < 5x /-4x                     4x + 2 > 5x /-4x

                      -2 < 9x / :9                            2 < x                                          2 > x

                       x > -2/9                                x > 2                                          x < 2                        

                        L1 = Ø                                L2 = Ø                          L3 = {x  R; 0 < x < 2 }    L = { x  R; 0 x < 2 }

12.                                                <  6 /·0,5x                       DB = { x  R ; x ≠ 0}

    x < 0                                                       x  0

| x – 4 | > 3x                                                 | x – 4 | < 3x

                                                                     0  x < 4                         x  4

                    -x + 4 > 3x /+x                   -x + 4 < 3x /+x                  x - 4 < 3x /-x

                            4 > 4x / :4                            4 < 4x /:4                        -4 < 2x

                            x < 1                                      x > 1                                   x > -2              

                L1 = {x  R; x < 0 }         L2 = {x  R; 1 < x < 4 }      L3 = {x R; x 4}    L={x R;x<0 und 1 x<∞} 

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14.) Funktionslehre

14.1) Lineare Funktionen 

-         

Aufgabe: Geben Sie die Steigung der Geraden an! Bestimmen Sie jeweils die Schnittpunkte der Geraden mit den Koordinatenachsen, zeichnen Sie die Gerade in ein kartesische Koordinatensystem ein, und zeichnen Sie ein Steigungsdreieck ein!

1.      f(x)  =  y  = 2x – 1                              m = 2              Sx(0,5|0)                     Sy(0|-1)

2.      f(x)  =  y  = -3x +                          m = -3             Sx(0,5|0)                     Sy(0|1,5)

3.      f(x)  =  y  = x -                          m = 2,5           Sx(0,2|0)                     Sy(0|-0,5)

4.      f(x)  =  y  =  -                               m = -0,5          Sx(0|0)                        Sy(0|0)

5.      f(x)  =  y  = - x + 1                         m = -0,25        Sx(4|0)                        Sy(0|1)

6.      f(x)  =  y  = x + 3                           m = 2/3           Sx(-4,5|0)                   Sy(0|3)

7.      f(x)  =  y  = x + 3                        m = -1,5          Sx(2|0)                        Sy(0|3)

8.      f(x)  =  y  = -2                                     m = 0               keiner                          Sy(0|-2)

9.      f(x)  =  y  = x + 2                                m = 1              Sx(-2|0)                       Sy(0|2)

10.  f(x)  =  y  = x -                         m = 0,6           Sx(2/3|0)                     Sy(0|-0,4)

 

14.5) Quadratische Funktionen

Aufgabe: Bestimmen Sie jeweils den Scheitel der Parabel und zeichnen Sie den Funktionsgraphen in ein kartesisches Koordinatensystem!

  1. f(x)  =  y  =                                     S(0|0)
  2. f(x)  =  y  =  x² - 1                              S(0|-1)
  3. f(x)  =  y  =  x² + 1,5                         S(0|1,5)
  4. f(x)  =  y  =  ( x – 1 )²                        S(1|0)
  5. f(x)  =  y  =  ( x + 2,5 )²                    S(-2,5|0)
  6. f(x)  =  y  =  ( x + 2 )² - 1                  S(-2|-1)
  7. f(x)  =  y  =  ( x – 3 )² + 2                 S(3|2)
  8. f(x)  =  y  =  -x²                                  S(0|0)
  9. f(x)  =  y  =  -x² - 1                             S(0|-1)
  10. f(x)  =  y  =  -x² + 4                            S(0|4)
  11. f(x)  =  y  =  -( x + 2 )²                      S(-2|0)
  12. f(x)  =  y  =  -( x – 2 )² + 4                S(2|4)
  13. f(x)  =  y  =  x² - 2                           S(0|-2)
  14. f(x)  =  y  =  - x² + 1                         S(0|1)
  15. f(x)  =  y  =  ( x – 2,5 )²                  S(2,5|0)

 

14.6) Nullstellen quadratischer Funktionen 

Aufgabe : Bestimmen Sie die Nullstellen  von f sowie die Koordinaten des Scheitelpunktes der Parabel und zeichnen Sie den Graph der Funktion!

  1.  f(x)  =  y  =  x² - 1                                         xN1 = -1           xN2 = 1             S(0|-1)

  2. f(x)  =  y  =  x² + 1,5                                     keine Nullstellen                       S(0|1,5)

  3. f(x)  =  y  =  x² + 2x + 1                               xN1/2 = -1                                  S(-1|0)

  4. f(x)  =  y  =  x² + 5x + 6,25                          xN1/2 = -2,5                              S(-2,5|0)

  5. f(x)  =  y  =  x² - 8x + 16                               xN1/2 = 4                                   S(4|0)

  6. f(x)  =  y  =  x² + 4x + 3                                xN1 = -3           xN2 = -1            S(-2|-1)

  7. f(x)  =  y  =  x² - 6x + 11                              keine Nullstellen                        S(3|2)

  8. f(x)  =  y  =  x² + 5x + 7,25                          xN1/2 = -2,5                               S(-2,5|0)

  9. f(x)  =  y  =  x² - 3x + 0,25                           xN1 = 1,5+√2   xN2 = 1,5-√2   S(1,5|-2)

  10. f(x)  =  y  =  x² + 6x + 7                                xN1 = -3+√2    xN2 = -3-√2     S(-3|-2)

  11. f(x)  =  y  =  -x² + 1                                       xN1 = -1            xN2 = 1             S(0|1)

  12. f(x)  =  y  =  -x² - 4                                        keine Nullstellen                        S(0|-4)

  13. f(x)  =  y  =  -x² - 4x – 4                               xN1/2 = -2                                   S(-2|0)

  14. f(x)  =  y  =  -x² + 5x – 6,25                         xN1/2 = 2,5                                 S(2,5|0)

  15. f(x)  =  y  =  -x² + 4x                                     xN1 = 0            xN2 = 4               S(2|4)

  16. f(x)  =  y  =  -x² - 2x + 1                               xN1 = -1+√2   xN2 = -1-√2       S(-1|2)

  17. f(x)  =  y  =  x² - 2                                      xN1 = -2           xN2 = 2               S(0|-2)

  18. f(x)  =  y  =  x² + 1                                     keine Nullstellen                         S(0|1)

  19. f(x)  =  y  =  x² - 2,5x + 3,125                  xN1/2 = 2,5                                 S(2,5|0)

  20. f(x)  =  y  =  x² + 1,5x + 1,125                 xN1/2 = -1,5                               S(-1,5|0)

  21. f(x)  =  y  =  x² - 2x                                    xN1 = 0            xN2 = 4              S(2|-2)

  22. f(x)  =  y  =  - x² - 2x                                  xN1 = 0            xN2 = -4             S(-2|2)

  23. f(x)  =  y  =  - x² + x + 4                             xN1 = -2           xN2 = 4             S(1|4,5)

  24. f(x)  =  y  =  - x² + 0,5x + 0,75                  xN1 = -1          xN2 = 3              S(1|1)

  25. f(x)  =  y  =  2x² - 2                                       xN1 = -1           xN2 = 1             S(0|-2)

  26. f(x)  =  y  =  -2x² + 4                                     xN1 = -√2        xN2 = √2          S(0|4)

  27. f(x)  =  y  =  2x² + 8x + 8                             xN1/2 = -2                                 S(-2|0)

  28. f(x)  =  y  =  -2x² + 12x – 18                        xN1/2 = 3                                  S(3|0)

  29. f(x)  =  y  =  2x² - 8x + 6                              xN1 = 1             xN2 = 3            S(2|-2)

  30. f(x)  =  y  =  -2x² - 8x – 6                             xN1 = -1           xN2 = -3           S(-2|2)

 

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16.) Absoluter Betrag

16.1) Der absolute Betrag

-          bestimmen Sie – falls möglich – den Betrag oder geben Sie unter Nutzung einer Fallunterscheidung den vereinfachten Term ohne Betragstriche an!

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17.)

17.1) 

 

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                     Tägliche Übungen - Mathematik   Klasse 11-II GK

         Nr.2

        a)    Fassen Sie zusammen: ab2 - 4a2b - 3b2a2 + 5ba + 8b2a - 2a2b2 + 7ba2 = -5a2b2 + 3a2b + 9ab2 + 5ab

        b)    Berechnen Sie den Wert des Term:           = 1,5

        c)    Lösen Sie die Gleichung:  x2 + 2x - 3  =  0  und prüfen Sie ihr Ergebnis mit dem Satz von Vieta!

                                                            x1 = -3        x2 = 1                (-3)·1  =  -3  w.A.        -3 + 1  =  -2  =  - (2)  w.A.

        d)    Stellen Sie die Gleichung:   V = 0,25π·r2·h    nach  r  um!        r  =  √(4V)/(π·h)

        e)    Benennen und erläutern Sie den Satz des Thales an einer geeigneten Skizze!

Jeder Peripheriewinkel über dem Durchmesser eines Kreises ist eine rechter Winkel (Sonderfall des     Peripheriewinkel-Zentriwinkel-Satzes).

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        Nr.3

        a)  Klammern Sie den größtmöglichen Faktor aus:     18x2y - 6xy + 30xy26xy·(3x - 1 + 5y)

        b)    Berechnen Sie den Wert des Term:       =  12

        c)    Lösen Sie die Gleichung:  0,75x2 - 6x + 5,25  =  0  !            x1 = 1    x2 = 7

        d)    Stellen Sie die Gleichung:   Whub = m·g·l·(1 - cosα)    nach  cosα  um!

                                                                cosα  =  1  -  Whub/(m·g·l)

        e)    Benennen und erläutern Sie den Sinussatz an einer geeigneten Skizze!

a/sinα  =  b/sinβ  =  c/sinγ     im beliebigen Dreieck liegt der größten Seite auch der größte Winkel gegenüber

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        Nr.4

        a)  Formen Sie mittels Binomischer Formeln um:  (5x - 1,5)(5x + 1,5) = 25x2 - 2,25     (3.Bin. Formel)

                                                                                            ( x2 - x + 0,25) = (x - 0,5)2    (Umkehrung der bin.Formel)

        b)    Berechnen Sie den Wert des Term:       =

        c)    Lösen Sie die Gleichung:  0,25x2  + 12,25  =  0  !           x2 = - 49        keine Lösung

        d)    Stellen Sie die Gleichung:   V = 2π r2 + 2π rh    nach  h  um!

                V - 2π r2 = 2π rh            h = (V - 2π r2)/2π r = V/2π r - r

        e)    Benennen und erläutern Sie die Winkelbeziehungen für den Sinus, Cosinus und Tangens in einem 

                rechtwinkligen Dreieck an einer geeigneten Skizze!

                sinα = Gegenkathete : Hypotenuse  = a/c

                cosα = Ankathete : Hypotenuse  =  b/c

                tanα = Gegenkathete : Ankathete  = a/b

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        Nr.5

        a)  Berechnen Sie für die Funktion  f(x) = x2 - 3   den Funktionswert an der Stelle xo + 2

             f(xo + 2) = (xo + 2)2 - 3 = xo2 + 4xo + 4 - 3 = xo2 + 4xo + 1

        b)  Berechnen Sie den Wert der Terme:    √1600 =  40                   -42 ·3 + 4·(-3)2 = - 48 + 36 = -12

        c)  Lösen Sie die folgende Gleichung:        |x - 4| = 1    Fallunterscheidung:

            für x > 4 folgt:   x - 4 = 1        x1 = 5

            für x < 4 folgt: -(x - 4) = 1        -x + 4 = 1        -x = - 3        x2 = 3

        Ergebnis: Lösung sind die zwei Zahlen, die von 4 den Abstand 1 haben !!!

        d)  Stellen Sie die Gleichung:   Q = m1·c·T1 + m2·c·T2        nach c um!

           Grundgedanke: Ausklammern (weil gesuchte Größe in mehreren Termen enthalten)                                            Q = c·(m1·T1 + m2·T2)            c = Q/(m1·T1 + m2·T2)

        e) Benennen und erläutern Sie den Nebenwinkelsatz an einer geeigneten Skizze!

            zwei benachbarte Winkel am Schnittpunkt zweier Geraden heißen Nebenwinkel und sind zusammen                  180° groß

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        Nr.6

        a)  Berechnen Sie für die Funktion  f(x) = x2 + 2x   den Funktionswert an der Stelle xo - 1

             f(xo - 1) = (xo - 1)2 + 2(xo - 1) =  = 

        b)  Berechnen Sie den Wert der Terme:    (1,25·105)/(5·10-3)

        c)  Lösen Sie die folgende Gleichung:        |x - 3| < 2    Fallunterscheidung:

            für x > 3 folgt:   x - 3 < 2        x1  

            für x < 3 folgt: -(x - 3) < 2              x2

        Ergebnis: Lösung sind alle die  Zahlen, die von 3 einen kleineren Abstand als 2 haben !!!

        d)  Stellen Sie die Gleichung:   u = (m1·v1+ m2·v2)/(m1+ m2)       nach v2 um!

            

        e) Benennen und erläutern Sie den Höhensatz (aus der Satzgruppe des Pythagoras) an einer geeigneten Skizze!

            

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                     Tägliche Übungen - Mathematik   Klasse 12-I GK

 

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                     Tägliche Übungen - Mathematik   Klasse 12-II GK

        Nr. 3

        a)

 

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                     Tägliche Übungen - Mathematik   Klasse 13-I GK

 

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                     Tägliche Übungen - Mathematik   Klasse 13-II GK

 

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