Question

Descompuneti in factori:
a) x^2+4x+4-y-2y-1

Answer 1

Banuesc ca e vorba de : x²+4x+4-y²-2y-1=(x²+4x+4)-(y²+2y+1)=(x+2)²-(y+1)²=
(x+2+y+1)(x+2-y-1)=(x+y+3)(x-y+1). 
Am folosit formulele : a²+2ab+b²=(a+b)², si a²-b²=(a+b)(a-b).