Bonjour,
Les "x" c'est toujours la lettre.
" * ": multiplication.
a)
12x - 8
= 3 * 4 * x - 4 * 2
= 4(3x - 2)
b)
6x² + 9x
= 3x * 2x + 3x * 3
= 3x(2x +3)
c)
4x(x + 2) + 3(x + 2)
= (x + 2)(4x + 3)
d)
-3y(y + 6) + (y + 6)(2y - 1)
= (y + 6)(-3y + 2y - 1)
= (y + 6)(- y - 1)
= - (y + 6)(y + 1)
e)
(x - 1)(5x + 4) + (x - 1)(3 + x)
= (x - 1)(5x + 4 + 3 + x)
= (x - 1)(6x + 7)
f)
(3x + 4)(5x - 1) - 3(3x + 4)
= (3x + 4)(5x - 1 - 3)
= (3x + 4)(5x - 4)
Bonne journée.
