Simplify (5n^4) ^-3. Assume n ≠ 0.

Since the exponent (-3) is negative, flip the expression to: 1 / (5n^4) ^3.

Notice how the negative exponent becomes positive as you flip it.

Now evaluate the powers in the denominator: 1 / ((5^3) (n^4) ^3

I separated the constant (5) from the variable (n) to show you how the powers are evaluated.

1 / (5x5x5) (nxnxnxn) (nxnxnxn) (nxnxnxn)

--> the power four means that there are 4 multiples of n in the parentheses. The power 3 corresponds to how many groups.

1 / (125) (n^12)

= 1/125n^12