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How to Use the SQRT Function

How to Use the SQRT Function in Excel

The SQRT function returns the square root of any given number.

Contents:


Syntax

= SQRT(number)

number - This is the numeric value you want to find the square root of. The number must be positive


note: Excel will return an #NUM error if a negative value is entered. Square roots of negative numbers are complex numbers, which this function cannot handle


Explanation

The SQRT function is part of the "Math and Trigonometry" group of functions within Excel.


This function is designed solely to calculate the square root of a given number.

Excel square root Function with Examples

What is a Square Root?

A square root of a number is a value that, when multiplied by itself, gives the original number. It's essentially the opposite operation of squaring a number.


For example:

  • The square root of 9 is 3, because 3×3=9.

  • The square root of 16 is 4, because 4×4=16


Square roots can be classified into two main types:

  1. Perfect Square Roots: These are the square roots of perfect squares, like 9, 16, 25, etc. The square roots of these numbers are integers.

  2. Imperfect Square Roots: These are the square roots of numbers that are not perfect squares, like 2, 3, 5, etc. The square roots of these numbers are irrational numbers, meaning they cannot be perfectly expressed as a simple fraction and have an infinite, non-repeating decimal representation.


Examples

How to Calculate the Length of a Square's Side

Imagine we have a table of measurements of different square fields. To find the length of one side, you can use the SQRT function since the area of a square is equal to the side length squared.

how to take square root in excel

In this example, if our area numbers begin in cell A2, if you input the formula:

 =SQRT(A2) 

into the cell next to the areas, Excel will calculate the square root of each area, giving us length of each squares' sides.

How to Calculate the Length of a Square's Side in excel

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