Réponses

  • Omnes
  • Modérateur confirmé
2014-03-04T23:20:39+01:00
Salut,

D(x) = (6x+3) * 7 - 7(5x-2)

1.Développer et réduire D(x)

D(x) = 7(6x+3)- 7(5x-2)
D(x) = 42x + 21 - 35x + 14
D(x) = 7x + 35

2. Factoriser D(x)

D(x) = 7(6x+3)- 7(5x-2)
D(x) = 7[(6x+3) - (5x-2)]
D(x) = 7(6x+3 - 5x + 2)
D(x) = 7(x + 5)

3. Résoudre D(x) = 0

D(x) = 0
7(x + 5) = 0

x + 5 = 0
x = -5

Bonne soirée !