Question

Answer 1

\(C=\dfrac{1}{x^2-9}:\dfrac{x+3}{x-3}\left(x\ne\pm3\right)\)

\(=\dfrac{1}{\left(x-3\right)\left(x+3\right)}.\dfrac{x-3}{x+3}\)

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

Answer 2

\(C=\dfrac{1}{x^2-9}:\dfrac{x+3}{x-3}\\ =\dfrac{1}{\left(x-3\right)\left(x+3\right)}:\dfrac{x+3}{x-3}\\ =\dfrac{1}{\left(x-3\right)\left(x+3\right)}.\dfrac{x-3}{x+3}\\ =\dfrac{x-3}{\left(x-3\right)\left(x+3\right)\left(x+3\right)}\\ =\dfrac{1}{\left(x+3\right)^2}\)