bonjour
a/ (9x-7)²=81x²-126x+49
b/(x+9)(11-5x)=11x-5x²+99-45x=-34x-5x²+99
c/(2x-3)(2x+3)=4x²+6x-6x-9=4x²-9
d/(11+8x)²=121+176x+64x²
e/(x+1)²+7x(2-x)=x²+2x+1+14x-7x²=-6x²+1+16x
f/(x+3)(2x-1)-3x(2x+5)=2x²-x+6x-3-6x²-15x=-4x²-10x-3
g=(4t+1)(4t-1)-(3t+2)²=16t²-4t+4t-1-9t²-12t-4=7t²-12t-5
h=2(s+5)(s-5)+(4s+3)²=2s²-10s+10s-50+16s²+24s+9=18s²+24s-41
i=(3x+4)²-(1-2x)(6+x)=9x²+24x+16-6-x+12x+2x²=11x²+35x+10
