Bonjour,
Réduire:
A= 6x²-4x+2-8x²+7x+6= -2x²+3x+8
B= x²+3x-4+2x²-5x+7= 3x²-2x+3
C= (6x-7)-(3-4x)= 6x-7-3+4x= 10x-10
D= -(8x²+7x)+(-6+3x²)-(-6x-3)= -8x²-7x-6-3x²= -5x²-x-3
E= 3(2x-1)= 6x-3
F= -5x(-4x+7)= 20x²-35x
G= 5x(-3x-6)-(-15x²+18x-6)= -15x²-30x+15x²-18x+6= -48x+6
H= -x(2-x)+(x²-2x)-(3x²-4)= -2x+x²+x²-2x-3x²+4= -x²-4x+4
