Bonjour,
Distributivité simple:
k(a + b) = ka + kb
Développer les expressions :
A = 2(3x + 6)
A = 2*3x + 2*6
A = 6x + 12
B = 6x(3 - 4x)
B = 6x*3 + 6x*(-4x)
B = 18x - 24x²
B = -24x² + 18x
C = -2(x + 6) - 5(-4x + 7)
C = -2*x + (-2)*6 - 5(-4x + 7)
C = -2x - 12 - [5*(-4x) + 5*7]
C = -2x - 12 - (-20x + 35)
C = -2x - 12 + 20x - 35
C = 18x - 47
* = multiplication
Bonne journée.
