Question

Answer 1

Bài 1:

a. $2x^2y-xy^2+xz^2-x^3=x(2xy-y^2+z^2-x^2)$
$=x[z^2-(x^2+y^2-2xy)]=x[z^2-(x-y)^2]=x(z-x+y)(z+x-y)$

b.

$xy^2+y^3-16x-16y=y^2(x+y)-16(x+y)=(x+y)(y^2-16)$

$=(x+y)(y-4)(y+4)$

Answer 2

Bài 2:

a. $5x(x-1)=x-1$

$\Leftrightarrow 5x(x-1)-(x-1)=0$

$\Leftrightarrow (x-1)(5x-1)=0$

$\Rightarrow x-1=0$ hoặc $5x-1=0$

$\Leftrightarrow x=1$ hoặc $x=\frac{1}{5}$

b.

$3x^2-48x=0$

$\Leftrightarrow 3x(x^2-16)=0$

$\Leftrightarrow 3x(x-4)(x+4)=0$

$\Rightarrow 3x=0$ hoặc $x-4=0$ hoặc $x+4=0$

$\Leftrightarrow x=0$ hoặc $x=4$ hoặc $x=-4$