November 5, 1999 - Mathematical Constants | WebReference

# November 5, 1999 - Mathematical Constants

 November 5, 1999Mathematical Constants Tips: November 1999 Yehuda Shiran, Ph.D.Doc JavaScript
JavaScript's built-in `Math` object provides various mathematics functionality and constants. It is a top-level, predefined JavaScript object, so it cannot be instantiated using the `new` operator. The properties of this object are well known mathematical constants:

 Property Description `Math.E` Returns Euler's constant, the base of natural logarithms. The `E` property is approximately equal to 2.718. `Math.LN10` Returns the natural logarithm of 10. The `LN10` property is approximately equal to 2.302. `Math.LN2` Returns the natural logarithm of 2. The `LN2` property is approximately equal to 0.693. `Math.LOG10E` Returns the base-10 logarithm of `E`, Euler's constant. The `LOG10E` property is approximately equal to 0.434. `Math.2E` Returns the base-2 logarithm of `E`, Euler's constant. The `LOG2E` property is approximately equal to 1.442. `Math.PI` Returns the ratio of the circumference of a circle to its diameter. The `PI` property is approximately equal to 3.14159. `Math.SQRT1_2` Returns he square root of 0.5, or one divided by the square root of 2. The `SQRT1_2` property is approximately equal to 0.707. `Math.SQRT2` Returns the square root of 2. The `SQRT2` property is approximately equal to 1.414.

The following function returns the area of a circle with a given radius:

``````function circle(r) {
return Math.PI * r * r;
}``````