Square root

A square root of a number x is a number y such that . Thus y is a square root of x if and only if x is the square of y. The square root of a number x is denoted . For instance, $\sqrt 4 = 2<\math>. When we consider only [[positive]] [[real number|reals]], the square root function is the [[inverse]] of the squaring function. However, this does not hold more generally because every positive real has two square roots, one positive and one negative. The notation <math>\sqrt x$ (Error compiling LaTeX. Unknown error_msg) is used for the positive square root.

It is also written as the one half exponent of the argument, so that squaring undoes this function just a multiplying by 2 undoes . Similar function can be generalized to any real number power as well as even complex powers!