Besoin d'aide pour cet exercice svp

A=4x
B=54x
C= .....
D= .....
E=15x
Désoler mais je sais que sa, j'espère t'avoir quand même aider. Bonne soirée

RAPPEL des identités remarquables : (a+b)²= a²+2ab+b²
 (a-b)²=a²-2ab+b²
(a-b)²(a+b)²=a²-b²

A=(9x-7)²=(9x)²-2*9x*7+7² =81x²-126x+49
B=(x+9)(11-5x)
=11x-5x*x+9*11-9*5x
=11x-5x²+99-45x
-5x²-34x+99

C=(2x-3)(2x+3) =(2x)²-3² =4x²-9

D=(11+8x)²=11²+2*11*8x+(8x)² =121+176x+64x²=64x²+176x+121

E=(x+1)²+7x(2-x)
=x²+2*x*1+1²+7x*2-7x*x
=x²+2x+1+14x-7x²
=-6x²+16x+1

F=(x+3)(2x-1)-3x(2x+5)
=x*2x-1*x+3*2x-3*1-3x*2x-3x*5
=2x²-x+6x-3-6x²-15x
=-4x²-9x-3

G=(4t+1)(4t-1)-(3t+2)²
=(4t)²-1²-((3t)²+2*3t*2+2²)
=16t²-1-9t²-12t-4
=7t²-12t-5

H=2(s+5)(s-5)+(4s+3)²
=2*(s²-5²)+(4s)²+2*4s*3+3²
=2*s²-2*25+16s²+24s+9
=2s²-50+16s²+24s+9
=18s²+24s-41

I=(3x+4)²-(1-2x)(6+x)
=(3x)²+2*3x*4+4²+(-1+2x)(6+x)
=9x²+24x+16-1*6-1*x+2x*6+2x*x
=9x²+24x+16-6-x+12x+2x²
=11x²+35x+10