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Square root of number

Excel formula: Square root of number
Generic formula 
=SQRT(number)
Summary 

To calculate the square root of a number in Excel, you can use the SQRT function. In the example shown, the formula in C5 (copied down) is:

=SQRT(B5)

The formula returns the square root of the numbers in column B.

Explanation 

The SQRT function is fully automatic and will return the square root of any positive number. For example, to get the square root of 25:

=SQRT(25) // returns 5

If you give SQRT a negative number, it will return a #NUM! error:

=SQRT(-4) // returns #NUM!

To treat a negative number like a positive number, you can wrap the number in the ABS function like this:

=SQRT(ABS(A1))

Exponentiation operator (^)

You can also get the square root of a number with Excel's exponentiation operator , a caret (^). The nth root a number can be written as a fractional exponent like this:

=A1^(1/n) // nth root

So, to return the square root of a number in A1, you can use a formula like this:

=A1^(1/2) // square root

The screen below a few examples in a worksheet:

Square root of number with exponent

Square root with POWER

You can get also get the square root with the POWER function by using 1/2 as the power argument:

=POWER(A1,1/2)

Square root of number with POWER function

POWER is a general function for raising a number to a given power.

Author 
Dave Bruns

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