what is the index of a radical?

Answer 1

Hi,
That's the number that is within the "V" shape of the radical sign. I'll make up a radical since I don't know if the word processor will reproduce a real one.
3 ___
V 27
(The 3 should be down inside the "V.")
Now, the 3 is the index, indicating to take the cube root, the 27 is called the radicand, and the entire expression is called a radical. The symbol is sometimes called a radical, but probably more properly should be called a radical sign.

Hope this helps.
FE