Đáp án:
Giải thích các bước giải:
$a, x^2-y^2-2x+2y=(x-y)(x+y) - 2(x-y)=(x-y)(x+y-2)$
$b, 2x+2y-x^2-xy=2(x+y)-x(x+y)=(2-x)(x+y)$
$c, 3a^2-6ab+3b^2-12c$
$=3(a^2-2ab+b^2) - 12c^2=3(a-b)^2-12c=3[(a-b)^2-4c^2]$
$=3(a-b-2c)(a-b+2c)$
$d, x^2-25+y^2+2xy=(x+y)^2-25=(x+y-5)(x+y+5)$
$e, a^2+2ab+b^2-ac-bc=(a+b)^2-c(a+b)=(a+b)(a+b-c)$
$f, x^2-2x-4y^2-4y=x^2-2x+1-4y^2-4y-1=(x-1)^2-(2y+1)^2$
$=(x-1-2y-1)(x-1+2y+1)=(x-2y-2)(x+2y)$
$g,x^2y-x^3-9y+9x=y(x^2-9)-x(x^2-9)=(y-x)(x+3)(x-3)$
$h, x^2(x-1)+16(1-x)=x^2(x-1)-16(x-1)=(x-1)(x-4)(x+4)$
$n, 81x^2-4=(9x-2)(9x-2)$
$m, xz-yz-x^2+2xy-y^2=z(x-y)-(x-y)^2=(z-x+y)(x-y)$
$p, x^2+8x+15=x^2+3x+5x+15=(x+3)(x+5)$
$k, x^2-x-12=x^2+3x-4x-12=(x-4)(x+3)$
Chúc bạn học tốt . Mình xin câu trả lời hay nhất nhé
