Question

b)x^2y/x-y-xy^2/x-y

c)2x/2x+y+y/y-2x

Answer 1

b: \(\dfrac{x^2y}{x-y}-\dfrac{xy^2}{x-y}\)(ĐKXĐ: x<>y)

\(=\dfrac{x^2y-xy^2}{x-y}\)

\(=\dfrac{xy\left(x-y\right)}{x-y}=xy\)

c: \(\dfrac{2x}{2x+y}+\dfrac{y}{y-2x}\)(ĐKXĐ: \(y\ne\pm2x\))

\(=\dfrac{2x}{2x+y}-\dfrac{y}{2x-y}\)

\(=\dfrac{2x\left(2x-y\right)-y\left(2x+y\right)}{\left(2x+y\right)\left(2x-y\right)}\)

\(=\dfrac{4x^2-2xy-2xy-y^2}{\left(2x+y\right)\left(2x-y\right)}=\dfrac{4x^2-4xy-y^2}{4x^2-y^2}\)