Question

Giúp em ạ

Answer 1

a: \(\dfrac{2-x}{3-y}=\dfrac{-\left(x-2\right)}{-\left(y-3\right)}=\dfrac{x-2}{y-3}\)

b: \(\dfrac{x^2-2x+1}{1-x^2}=\dfrac{\left(x-1\right)^2}{\left(1-x\right)\left(1+x\right)}=\dfrac{1-x}{x+1}\)

c: \(\dfrac{\left(x+2\right)\left(x+1\right)}{x^2-1}=\dfrac{\left(x+2\right)\left(x+1\right)}{\left(x-1\right)\left(x+1\right)}=\dfrac{x+2}{x-1}\)

d: \(\left(x^2-3x+2\right)\left(x+1\right)=\left(x-2\right)\left(x-1\right)\left(x+1\right)=\left(x-1\right)\left(x^2-x-2\right)\)

=>\(\dfrac{x^2-x-2}{x+1}=\dfrac{x^2-3x+2}{x-1}\)