Algebra/Square Root is Positive

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Algebra

Squire Root is Positive[edit]

We often say that \sqrt{x} is the positive number, which when squared is equal to x. If x>0 this is perfectly correct, but if x = 0 then \sqrt{x} = \sqrt{0} = 0 which is not positive. So to be technically correct (which is part of the fun of math) we should say that \sqrt{x} is the non-negative number, which when squared is equal to x.

If it is needed to express that a square root may be both positive and negative, you will see \plusmn \sqrt{x}.