Question

Va rog mult ex 4.Dau coroana!!!!!!!!!!!!!!!!!!!!!!!

Answer 1

Formula de calcul prescurtat folosita este
a^2 - b^2 = (a-b)(a+b)

a)(3x-2-4x)(3x-2+4x)=(-x-2)(7x-2)=-(x+2)(7x-2)=(x+2)(2-7x)
b)(3x-6-2x)(3x-6+2x)=(x-6)(5x-6)
c)9x^2(x+1)-4(x+1)=(x+1)(9x^2-4)=(x+1)(3x-2)(3x+2)
d)(2x-10-x+1)(2x-10+x-1)=(x-9)(3x-11)
e)(x^2+3x+1-x-3)(x^2+3x+1+x+3)=(x^2+2x-2)(x^2+4x+4)=(x^2+2x-2)(x+2)^2
f)(x^2+2x-3-x+1)(x^2+2x-3+x-1)=(x^2+x-2)(x^2+3x-4)=(x+2)(x-1)(x+4)(x-1)=(x+2)(x+4)(x-1)^2