Getting to the Root of Things

Problem

You need to compute the square root of an expression. Moreover, you'd like to know how to compute other roots, like the cube root, of an expression.

Solution

Use the SQRT function for taking square roots and use the POWER function or the ^ operator to handle other roots.

Discussion

The syntax for the square root function is simply =SQRT(n), where n is a number or an expression containing cell references that evaluates to a number. SQRT returns the positive square root of n.

Excel does not provide other specific functions for taking cube roots and so on; however, you can take such roots using the POWER function or the ^ operator, which performs the same function as the POWER function. To take the cube root of a number, use =POWER(n, 1/3) or n^(1/3). Taking the cube root of a number is the same as raising the number to the power 1/3. So for any other roots you may find in your calculations, you can raise a number to the reciprocal of the desired root using POWER or ^.

See Also

See Recipe 7.4 for more information related to the POWER function. Also, take a look at Recipe 1.9 for more on ^ and other operators.