The function SuperPower receives two inputs, x and n$,$ and should return x$^(4$n$-2).$ x is a real number and n is positive integer

SuperPower $($x$,$n$)$

If n $=1,$ then return $($x$^2)$

y :$=$ SuperPower$($x$,$n$-1)$

Return$(?)$

The correctness of algorithm SuperPower$($x$,$n$)$ is proven by induction on n$.$ Suppose that the inductive hypothesis is that SuperPower$($x$,$k$)$ returns x$^(4$k$-2).$ What fact must be proven in the inductive step?