Explications étape par étape:
j'espere que sa pourrais t'aidee
c= (4+8x)
=2(2+4x) forme factorise
e=(5+9x)(5-9x)
= 5×5 -9x×9x
=25-81x²
f=(7+4x)(-4x+7)
= (7+4x)(+7-4x)
= 7×7 - 4x×4x
= 49 - 16x²
a=25 - x²
=(5-x)(5+x)
b = (x+1)²
= x²+2x+1
d= 4x²-12x+9
= 2x×2x - 2×2×3 -3×-3
= (2X- 3)²
f= (8-3x)²
= 8×8 +2×8-3x -3x×-3x
= 64 -48+9x²
c= (7x+10)(7x-10)
= 7X×7X +10×-10
= 49X² -100
e= (4X-4)(4X+4)
= 4X×4X -4×+4
= 16X²-16