DIVA17
Answered

15 Factorise les expressions suivantes :
a. (2x - 3)(3x + 7) - 2x + 3
b.(5x - 4)2 - 5x + 4
c. (2x + 7)2 - 2x - 7 + (3x - 1)(2x + 7)
d. (5x + 2)(2x + 1) + (-2x - 1)2

Sagot :

A) (2x-3)(3x+7) - 2x + 3
= (2x+3) X (3x+7)-(2x-3)
= (2x-3) X (3x + 7-1)
= (2x-3) X (3x+6)
= (2x-3) x3 (x+2)
= 3 (2x-3) x (x+2)