Question

giúp tớ mấy câu in đậm nha !

Answer 1

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

b: \(=\dfrac{2x-10}{x-5}=2\)

c: \(=\dfrac{x-2-3x+6}{\left(x-2\right)\left(x+2\right)}=\dfrac{-2x+4}{\left(x-2\right)\left(x+2\right)}=\dfrac{-2}{x+2}\)

Answer 2

\(b,\dfrac{2x}{x-5}-\dfrac{10}{x-5}=\dfrac{2\left(x-5\right)}{x-5}=2\)

\(h,=\dfrac{5\left(x+2\right)}{4\left(x-2\right)}.\dfrac{-4\left(x-2\right)}{x+2}=-5\)

\(m,\dfrac{5x-15}{4x+4}:\dfrac{x^2-9}{x^2+2x+1}=\dfrac{5\left(x-3\right)}{4\left(x+1\right)}.\dfrac{\left(x+1\right)^2}{\left(x-3\right)\left(x+3\right)}=\dfrac{5\left(x+1\right)}{4\left(x+3\right)}\)