The Math.cos() static method returns the cosine of a number in radians.
Syntax
Math.cos(x)
Parameters
x- : A number representing an angle in radians.
Return value
The cosine of x, between -1 and 1, inclusive. If x is Infinity, -Infinity, or NaN, returns NaN.
Description
Because cos() is a static method of Math, you always use it as Math.cos(), rather than as a method of a Math object you created (Math is not a constructor).
Examples
Using Math.cos()
Math.cos(-Infinity); // NaN
Math.cos(-0); // 1
Math.cos(0); // 1
Math.cos(1); // 0.5403023058681398
Math.cos(Math.PI); // -1
Math.cos(2 * Math.PI); // 1
Math.cos(Infinity); // NaN