: Mathématiques: square root

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square root

In mathematics, a square root of a number $x$ is a number $y$ such that ${\\displaystyle y^{2}=x}$ ; in other words, a number $y$ whose square (the result of multiplying the number by itself, or ${\\displaystyle y\\cdot y}$ ) is $x$ . For example, 4 and −4 are square roots of 16 because ${\\displaystyle 4^{2}=(-4)^{2}=16}$ .
(Wikipedia, The Free Encyclopedia, https://en.wikipedia.org/wiki/Square_root)