What is the fallacy of this proof?

Question

I recently was working with square roots and came across this-

$({\sqrt -1})$$=-1^\frac12$$=-1^\frac24$$=(-1^2)^\frac14$$=1^\frac14$$=1$

I understand that this is not true,but despite repeated attempts failed to prove it wrong.Can someone please point out the fallacy in this proof.Thanks in advance.

Answer 1

The fourth root of $1$ has four solutions: $1$, $-1$, $j$ and $-j$. The last two solutions are identical to the two solutions of the square root of $-1$.

Answer 2

The property that $(a^n)^m=(a^m)^n=a^{mn}$ is only defined for real numbers. But $\sqrt{-1}=i$ is a complex number.