# fractional exponents error: "negative number to a fractional power not real"

Hi. I'm having a problem with fractional exponents and higher order roots in sage.

If I put `(-2)** (6/2), sqrt((-2)** 6)`

, the result is `(-8, 8)`

. That's wrong, since `sqrt[ (-2)**6 ] = (-2) * (-2) * (-2) = -8`

. Does anyone know why this is happening, please?

I need to plot a function like `V(x) = x^[ (2n+1)/n ]`

, where n is interger. However, sage returns the error 'negative number to a fractional power not real' and plot only the positive branch.