Math.sqrt()

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This feature is well established and works across many devices and browser versions. Its been available across browsers since July 2015.

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The Math.sqrt() static method returns the square root of a number. That is

x0,.()=x=the unique y0 such that y2=x\forall x \geq 0,\;\mathtt{\operatorname{Math.sqrt}(x)} = \sqrt{x} = \text{the unique } y \geq 0 \text{ such that } y^2 = x

Try it

function calcHypotenuse(a, b) {
  return Math.sqrt(a * a + b * b);
}

console.log(calcHypotenuse(3, 4));
// Expected output: 5

console.log(calcHypotenuse(5, 12));
// Expected output: 13

console.log(calcHypotenuse(0, 0));
// Expected output: 0

Syntax

Math.sqrt(x)

Parameters

x: A number greater than or equal to 0.

Return value

The square root of x, a nonnegative number. If x < 0, returns NaN.

Description

Because sqrt() is a static method of Math, you always use it as Math.sqrt(), rather than as a method of a Math object you created (Math is not a constructor).

Examples

Using Math.sqrt()

Math.sqrt(-1); // NaN
Math.sqrt(-0); // -0
Math.sqrt(0); // 0
Math.sqrt(1); // 1
Math.sqrt(2); // 1.414213562373095
Math.sqrt(9); // 3
Math.sqrt(Infinity); // Infinity