In mathematics

Mathematics

Mathematics is the study of quantity, space, structure, and change. Mathematicians seek out patterns and formulate new conjectures. Mathematicians resolve the truth or falsity of conjectures by mathematical proofs, which are arguments sufficient to convince other mathematicians of their validity...

, a square root of a number x is a number r such that r² = x, or, in other words, a number r whose square (the result of multiplying the number by itself, or r × r) is x. For example, 4 is a square root of 16 because 4² = 16.

Every non-negative real number

Real number

In mathematics, a real number is a value that represents a quantity along a continuum, such as -5 , 4/3 , 8.6 , √2 and π...

 x has a unique non-negative square root, called the principal square root, which is denoted by , where is called radical sign.