Sagot :
1. a) ( x+4 ) ( x-6 ) = x² + 6x * 4x - 24 = x² + 24x - 24
b) ( -1+x ) ( x-2 ) = -1x + (-1) + 2 * x² - 2x = -3x + 1 + x²
2. x = 0
a) ( x+4 ) ( x-6) = ( 0+4 ) ( 0-6 ) = 4*6 = 24
b) ( -1+x ) ( x-2 ) = ( -1+0 ) ( 0-2 ) = -1* 2 = -2
x = 1
a) ( x+4 ) ( x-6 ) = ( 1+4 ) ( 1-6 ) = 5*(-5) = -25
b) ( -1+x ) ( x-2 ) = ( -1+1 ) ( 1-2 ) = 0 * (-1) = 0
J'espère t'avoir aidé ! :)
1) (x+2)(x+3)
=x²+5x+6
(x+5)(x+7)
=x²+12x+35
(x+4)(x-6)
=x²-2x-24
(x-1)(x-2)
=x²-3x+2
2) (x+2)(x+3)=0
donc x=-2 ou x=-3
(x+5)(x+7)=0
donc x=-5 ou x=-7
(x+4)(x-6)=0
donc x=-4 ou x=6
(x-1)(x-2)=0
donc x=1 ou x=2