First, express x^-4 with a positive exponent. You can do this by putting it in the denominator of a fraction.
(4 • 1/x^4)^-3
Next, multiply the terms in the parentheses.
(4/x^4)^-3
Express ^-3 as a positive exponent by finding the reciprocal of the fraction inside the parenthesis.
(x^4/4)^3
Then, distribute the power into the parentheses. (Numerator and denominator)
x^12/64
Hope this helps!