I can't figure out how to do this problem, please help.

4x^(-4/3)

Step-by-step explanation:

Let's rewrite the powers in fraction form :

8/(8x^4)^(1/3)

now simplify the denominator : (8x^4)^(1/3)

(8x^4)^(1/3) = 2x^(4/3)

8/2x^(4/3)

4/x^(4/3)

Now we can make it so there are no denominators by flipping it.

4/x^(4/3) becomes 4x^(-4/3)

correct answer:

i^31 = -i