c le 56.57.merci c urgent

a = (x-1)²

b = (6-7x)(6+7x)

c =(2x-3)(2x+3)

d =(x-5)²

e = (t+2)²

f =(t+7)²

exercice 57

a = (2a-1 -3a-2)(2a-1+3a+2)
a =(-a-3)(5a+1)

b = (3-8x)(3+8x)

c =(3+5x)²

d =(5x-3)²

e =(4x-1)²

f = (3t+4)²