Mathematics

Problem

For non-zero

m

and

n

, which expression is equal to

\left(\dfrac{m}{n}\right)^{-2}

? a)

-\dfrac{m^{2}}{n^{2}}

\dfrac{m^{2}}{n^{2}}

\dfrac{n^{2}}{m^{2}}

\dfrac{n}{m}