Bonjour,
A: (3x+2)x 5
= 15x +10
B: 7 x (4x-1)
28x -7
C: (3-7x)x 2x
= 6x - 14x²
Exercice 3
Développer et réduire les expressions suivantes :
A = 3(4x- 5) - (2x - 8)
=12x -15 -2x +8
= 10x -7
B = -(-3x + 5) - 4(8 - 2x) =
3x -5 -32 +8x
=11x -37
C = -2(2x - 3) + 4x + 3(2x - 5)
= - 4x +6 +4x +6x -15
= 6x - 9
D = -x - (8 - 7x) +5x =
-x -8 +7x +5x
= 11x -8
E = (4x– 7) - (2x – 5) + 2(8 -4x)
= 4x-7-2x+5+16 -8x
= -6x +14