Exercice n°1 : Développer et réduire les expressions suivantes :
A = 10 - (2x + 5)
=
-
B = 10 + (2x - 5)
C = 7+ 3(2x - 6)
D = 8x + (2x - 2)(3x + 1)
E = (x + 8)(x – 8) =
F = (x + 6)2 =
Pouvez vous m’aider svp


Sagot :

LEAFE

A = 10 - (2x +5)

A = 10 -2x - 5

A =  -2x + 5

B = 10 + (2x - 5)

B = 10 + 2x -5

B = 2x + 5

C = 7 + 3(2x -6)

C = 7 + 3 * 2x + 3 * (-6)

C = 7 + 6x -18

C= 6x  - 11

D = 8x + (2x -2)(3x + 1)

D = 8x + 2x * 3x + 2x * 1 -2 * 3x -2 * 1

D = 8x + 6x² + 2x - 6x -2

D = 6x² + 10x - 6x - 2

D = 6x² + 4x - 2

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

E = x² - 8²

E = x² - 64

F = (x + 6) * 2

F = x * 2 + 6 * 2

F = 2x + 12