Bonjour,
Développer:
A= (x+8)(2x-5)+7x= 2x²+16x-5x-40+7x= 2x²+18x-40
C= 12x²+9x+(-5x+2)(7x-4)= 12x²+9x+(-35x²+14x+20x-8)= 12x²+9x-35x²+34x-8
= -23x²+43x-8
E= (x+9)(x- 5)+(2x+3)= x²+9x-5x-45+2x+3= x²+6x-42
G= (6x-7)(x-4)-(10x-8)= 6x²-7x-24x+28-10x+8= 6x²-41x+36
I = (-4x+3)(2-5x)+6(x²-x+7)= -8x+6+20x²-15x+6x²-6x+42= 26x²-29x+48
K= (5x+7)(3x-8)-(-5x-2) +10(x²-4)=15x²+21x-40x-56+5x+2+10x²-40=25x²-14x-94
