Problema Solution

Find all complex numbers whose sixth power is equal to 64

Answer provided by our tutors

let 'x' represent the a number whose sixth power is equal to 64


x^6 = 64


x^6 - 64 = 0


factoring the equation we can write:


(x - 2)(x + 2)(x^2 + 2x + 4)(x^2 - 2x + 4) = 0


click here to see the step by step factoring:


Click to see all the steps



the linear factors give two solutions:


x1 = 2


x2 = -2


solving the quadratic factors we find the complex roots:


(x^2 + 2x + 4) = (x + 1)^2 + 3 = (x + 1 + i√3) (x + 1 - i√3)


x3 = -1 - i√3


x4 = -1 + i√3


(x^2 - 2x + 4) = (x - 1)^2 + 3 = (x - 1 + i√3) (x - 1 - i√3)


x5 = 1 - i√3


x6 = 1 + i√3


the complex numbers whose sixth power is equal to 64 are:


1 + i√3, -1 + i√3, 1 - i√3, -1 - i√3