Réponse :
bonjour
Explications étape par étape :
A=(8x+8)(8x-8)
=64x²-64x+64x-64
=64x²-64
B=(5x-6)²
=25x²-30x-30x+36
=25x²-60x+36
C=(3x+9)²
=9x²+27x+27x+81
=9x²+54x+81
D=(x+10)(9x-10)
=9x²-10x+90x-100
=9x²+80x-100x
E=-(9x-4)²+(3x+4)
=-(81x²-36x-36x+16)+3x+4
=-81x²+72x-16+3x+4
=-81x²+75x-12
F=(x+7)(-2x-5)+(6x-2)(6x+2)
= -2x²-5x-14x-35+36x²-4
=34x²-19x-39
A=(10x-7)(10x-7)
=100x²-70x-70x-49
=100x²-140x-49
B=(6x-8)²
=36x²-48x-48x+64
=36x²-96x+64
C=(x+6)²
=x²+6x+6x+36
=x²+12x+36
D=(-10x+5)(-7x-9)
=70x²+90x-35x-45
=70x²+55x-45
E= -(-7x+90)(6x+3)-(5x+10)
=-(-42x²-21x+540x+270)-5x-10
=42x²+21x-540x-270-5x-10
=42x²-524x-280
F=-(3x+10)(3x-10)+(2x-9)²
=-(9x²-100)+4x²-18x-18x+81
=-9x²+100+4x²-36x+81
=-5x²+181-36x
bonne journée