Đáp án:
Giải thích các bước giải:
$\text{Bài 1:}$
$\text{a, $x^{4}$ + 2x³+x²}$
$\text{= $x^{4}$ +x³+x³+x²}$
$\text{=x³(x+1)+x²(x+1)}$
$\text{=(x³+x²)(x+1)}$
$\text{=x²(x+1)(x+1)}$
$\text{=x²(x+1)²}$
$\text{b, x³-x+3x²y+3xy²+y³-y}$
$\text{=(x+y)³-(x+y)}$
$\text{=(x+y)[(x+y)²-1]}$
$\text{=(x+y)(x+y-1)(x+y+1)}$
$\text{c, 5x²-10xy+5y²-20z²}$
$\text{=5(x²-2xy+y²-4z²)}$
$\text{=5[(x-y)²-4z²]}$
$\text{=5(x-y-2x)(x-y+2z)}$
$\text{Bài 2:}$
$\text{a, x²+5x-6}$
$\text{= x²+6x-x-6}$
$\text{= x(x+6)-(x+6)}$
$\text{=(x-1)(x+6)}$
$\text{b, 5x²+5xy-x-y}$
$\text{= 5x(x+y)-(x+y)}$
$\text{= (5x-1)(x+y)}$
$\text{c, x²+4x+3}$
$\text{=x²+x+3x+3}$
$\text{= x(x+1)+3(x+1)}$
$\text{= (x+3)(x+1)}$
$\text{d, 2x²+3x-5}$
$\text{= 2x²-2x+5x-5}$
$\text{= 2x(x-1)+5(x-1)}$
$\text{= (2x+5)(x-1)}$
$\text{e, 16x-5x²-3}$
$\text{= -5x²+16x-3}$
$\text{= -5x²+15x+x-3}$
$\text{= -5x(x-3)+(x-3)}$
$\text{=(-5x+1)(x-3)}$
Xin hay nhất ạ!
