Question

Answer 1

mờ quá

Answer 2

\(A=\dfrac{x\left(x-y\right)}{y}\cdot\dfrac{y\left(x+y\right)}{x\left(x-y\right)}\cdot\dfrac{x^2+1}{x^2+2}=\dfrac{x^2+1}{x^2+2}\)

\(B=\dfrac{x-1}{3x}\cdot\dfrac{x\left(x+1\right)}{\left(x-1\right)\left(x+1\right)}\cdot\dfrac{x^2+x+1}{\left(x+1\right)^2}\)

\(=\dfrac{1}{3}\cdot\dfrac{\left(x^2+x+1\right)}{x+1}=\dfrac{x^2+x+1}{3x+3}\)