The square root operator is a special case of the radical operator that returns the square root of a number. The square root of an expression is a value, that when multiplied by itself is equal to the initial expression. For example, the square root of is equal to as shown in the quation below.
The square root operator returns both positive and negative roots of a number. This is expressed using the (plus-minus) symbol as shown below. Sometimes, the absolute value notation is used to explicitly indicate that the positive square root is wanted.
Here are the first five number that correspond to the roots through .
The square root of a number can be visualized as finding the side-length of a square with an area equal to the number. For example, the square with an area of and a side length of as visualized below.