34 Développer et réduire les expressions suivantes. A = (7x + 3)(x + 5) B = (5 - 2x)(3x - 6) C = (3x + 1)(-5x + 3) D = (7x - 2)2 E = (-4x - 2)(-x + 8) F = 4(2x

Bonjour,

A = (7x + 3)(x + 5)=

7x² +35x +3x +15=

7x² +38x +15

B = (5 - 2x)(3x - 6)=

15x -30 -6x² +12x=

-6x² +27x -30

C = (3x + 1)(-5x + 3) =

-15x² +9x -5x +3=

-15x² +4x +3

D = (7x - 2)2=

14x -4

E = (-4x - 2)(-x + 8)=

4x² -32x +2x -16=

4x² -30x -16

F = 4(2x - 1)(-x + 3)=

(8x -4) ( -x+3)=

-8x² +24x +4x -12=

-8x² =28x  -12