Question

What is the index of a radical?

Answer 1

The index of the radical indicates the root of the radicand which is to be found.

The index is equivalent to the denominator of a rational exponent.

Taking an odd index of a negative radicand will yield a negative value.

Taking an even index of a negative radicand will invoke complex/imaginary values.

Answer 2

square root has an index 2
cube root has index 3 and so on.
\[\sqrt[n]{k}\]
n is the index
k is the radicand