Sign of fractional exponent

45 Views Asked by At

What is the sign of $-1^{\frac{2}{3}}$? I thought it was positive 1 because it involves squaring, but that doesn't seem to be the case. Why?

2

There are 2 best solutions below

0
On

If you rewrite it, it becomes $\sqrt[3]{(-1)^2}$.

$(-1)^2 = 1$ and $\sqrt[3]{1} = 1$

So positive 1.

0
On

$x^y$ is not defined for negative $x$ and real $y$. Otherwise, we would have $(-1)^{1/3} = -1$, but $(-1)^{2/6}=1$.