Verified answer

Bonsoir,

Développer et réduire les expressions suivantes.

A=(2x-3)(7-x).

A = 14x - 2x^2 - 21 + 3x

A = -2x^2 + 17x - 21

B=(x+y)(2x-y)

B = 2x^2 - xy + 2xy - y^2

B = 2x^2 + xy - y^2

C=(x-7)(2+y).

C = 2x + xy - 14 - 7y

D=(x-1)(1-x)

D = x - x^2 - 1 + x

D = -x^2 + 2x - 1

E=3(3a+4)^2

E = 3(9a^2 + 24a + 16)

E = 27a^2 + 72a + 48

F=-5(4-b)^2

F = -5(16 - 8b + b^2)

F = -80 + 40b - 5b^2

F = -5b^2 + 40b - 80