\(a;\dfrac{5x+10}{25x^2+50}=\dfrac{5\left(x+2\right)}{25\left(x^2+2\right)}=\dfrac{x+2}{5\left(x^2+2\right)}\)
\(b;\dfrac{x}{x^2-1}=\dfrac{x}{\left(x-1\right)\left(x+1\right)}=\dfrac{x\cdot\left(x+1\right)}{\left(x-1\right)\left(x+1\right)^2}\\ \dfrac{1}{x^2+2x+1}=\dfrac{x-1}{\left(x-1\right)\left(x+1\right)^2}\)


