Although addition and multiplication are commutative, exponentiation is not: swapping the value in the base with the value in the exponent will produce a **different** result (unless, of course, they are the same value):

Therefore, two different inverse functions are needed to solve equations that involve exponential expressions:

– roots, to undo exponents

– logarithms, to undo bases

Just as there are many versions of the addition function (one for each number you might wish to add), and many versions of the “logarithm” function (each with a different base), there are many versions of the “root” function: one for each exponent value to be undone.

### Notation

The symbol for a root is , and is referred to as a “**radical**“. It consists of a sort of check mark on the left, followed by a horizontal line, called a “vinculum”, that serves as a grouping symbol (like parentheses) to Continue reading Roots and Rational Exponents: a summary