Since the denominator of each of those rational exponents is a 4, that means that the radical is a 4th root. The numerator of each exponent serves as the power on the given base. For example,
can be rewritten as
The little number that sits outside the radical, resting in the bend, is called the index. Our index is 4 (same as saying the 4th root). Put everything under the 4th root and let the numerator be the powers on each base: