of a number a
expresses another number that, when multiplied by itself n
times, will result in a.
Aside from the radical symbol, the notation is made up of the a
and the n.
The resulting number is commonly called a radical
. For example, the radical expression
simplifies to 2
multiplied by itself 4
times equals 16.
The general expression
represents a number which equals a
when multiplied by itself n
For any a
is defined as the
root of a.
Note that a root with an index is defined only for numbers. Therefore, if n
is even, then a
must be non-negative.
Just as with , the most common roots have special names: and have an index of 2 and 3, respectively.