Question

Descompuneti in factori: a) (x+1) totul la a doua-9; b) (x+2)totul la a doua -25; c) (x-3) totul la a doua -4; d) (x-5) totul la a doua -16; e) (y-2) totul la a doua -16. Va rog ajutati-ma

Answer 1

a² - b² = (a-b)(a+b)
a) (x+1)²-9 = (x+1)²-3² = (x+1+3)(x+1-3) = (x+4)(x-2)
b) (x+2)² -25 = (x+2)² - 5² = (x+2+5)(x+2-5) = (x+7)(x-3)
c) (x-3)² -4 = (x-3)²-2² = (x-3+2)(x-3-2) = (x-1)(x-5)
d) (x-5)² -16 = (x-5)² - 4² = (x-5-4)(x-5+4)= (x-9)(x-1)
e) (y-2)² -16 = (y-2)² - 4² = (y-2-4)(y-2+4) = (y-6)(y+2)