In mathematics, a square root of a number x is a number r such that r = x, or, in other words, a number r whose square (the result of multiplying the number by itself) is x.
Every non-negative real number x has a unique non-negative square root, called the principal square root, which is denoted with a radical sign as . The square root can also be written in exponent notation, as x. For example, the principal square root of 9 is 3, denoted , beca...
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In mathematics, a square root of a number x is a number r such that r = x, or, in other words, a number r whose square (the result of multiplying the number by itself) is x.
Every non-negative real number x has a unique non-negative square root, called the principal square root, which is denoted with a radical sign as . The square root can also be written in exponent notation, as x. For example, the principal square root of 9 is 3, denoted , because 3 = 3 × 3 = 9 and 3 is non-negative. The principal square root of a positive number, however, is only one of its two square roots.
Every positive number x has two square roots. One of them is , which is positive, and the other , which is negative. Together, these two roots are denoted . Square roots of negative numbers can be discussed within the framework of complex numbers. More generally, square roots can be considered in any context in which a notion of "squaring" of some mathematical objects is defined (including algebras of matrices,...
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