Answer
3$x^{-2}$ and 3$x^{2}$ are not reciprocals.
Work Step by Step
The reason why 3$x^{-2}$ and 3$x^{2}$ are not reciprocals is because the reciprocal of 3$x^{2}$ is $\frac{1}{3x^{2}}$.
However when we change the exponent of 3$x^{-2}$ from negative to positive , it becomes $\frac{3}{x^{2}}$.
Thus the the reciprocal of 3$x^{2}$ doesn't equal 3$x^{-2}$.
