bonjour,pouvez vous m’aider pour ces calculs merci d’avance

Réponse:

EXERCICE:1

A=3(4x+7)+4(2x-9)

=3×4x+3×7+4×2x+4×(-9)

=12x+21+8x+(-36)

=12x+8x+21+(-36)=20x+(-15)

B=7×(2x-5)-x(2x-5)

=7×2x+7×-5+(-x×2x-x×(-5)

=14x-35x-2x²+5x

=2x²+14x+5x-35

=2x²+19x-35

C=(2x+5)(3x+7)

=2x×3x+2x×7+5×3x+5×7

=6x²+14x+15x+35

=6x²+29x+35

D=(2x-5)(3x-2)

=2x×3x+2x×(-2)-5×3x+(-5)×(-2)

=6x²+x-15x+10

=6x²-14x+10

EXERCICE:3

H=(x+5)²

=x²+2(x×5)+5²

=x²+10x+25

I=(4x+6)²

=(4x)²+2(4x×6)+6²

=16x²+48x+36

J=(x-5)²

=x²-2(x×5)+5²

=x²-10x+25