What is the 5th root of -1?

Answer 1

6

Answer 2

The only real 5 th root is -1.

But there are 4 complex roots. These are:

cos(x) + i*sin(x) where x = pi/5, 3*pi/5, 7*pi/5 and 9*pi/5 are angles measured in radians and i is the imaginary square root of -1.