FASHIONBOUTIK62
Answered

Bonjour j'ai besoin d'aide svp pour c'est 2 exercices de maths merci

Exercice 3
Factoriser les expressions suivantes :
= −49 + 21
= 8²+ 2
= ( − 3)(2 + 1) + ( − 3)(5 − 7)
= (5 + 1)(3 − 5) − ( − 2)(5 + 1
= ² + 18 + 81
= ²− 12 + 36

Exercice 4
Résoudre les équation-produit suivantes :

a) (x+1)(x-8)=0
b) (5x-3)(6+x)=0
c) (11-8x)(3x+7)=0
d) 2x(3x+2)(3x-1)=0

Sagot :

RAYANTALHANI7
Exercice 4 :

a) x+1 = 0 x-8 = 0
x+1-1 = 0-1 x-8+8 = 0+8
x = -1 x = 8

b) 5x-3 = 0 6+x = 0
5x-3+3 = 0+3 x+6-6 = 0-6
5x = 3 x = 6
5x / 5 = 3 / 5
x = 3 / 5
x = 0,6

c) 11-8x = 0 3x+7 = 0
-8x+11-11 = 0-11 3x+7-7 = 0-7
-8x = -11 3x = -7
-8x / 8 = -11 / 8 3x / 3 = -7 / 3
x = -11 / 8 x = -7 / 3
x = -1,375

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

3x-1 = 0
3x-1+1 = 0+1
3x = 1
3x / 3 = 1 / 3
x = 1 / 3