#  Chapter 21JavaScript Reference # Math Object

## Name

Math Object---placeholder for mathematical functions and constants

## Availability

Navigator 2.0, Internet Explorer 3.0

## Synopsis

```Math.constant
Math.function()
```

## Constants

E

the constant e, the base of the natural logarithm.

LN10

the natural logarithm of 10

LN2

the natural logarithm of 2

LOG10E

the base-10 logarithm of e

LOG2E

the base-2 logarithm of e

PI

the constant pi

SQRT1_2

1 divided by the square root of 2

SQRT2

the square root of 2

## Functions

abs()

compute an absolute value

acos()

compute an arc cosine

asin()

compute an arc sine

atan()

compute an arc tangent

atan2()

compute the angle from the X axis to a point

ceil()

round a number up

cos()

compute a cosine

exp()

compute an exponent of e

floor()

round a number down

log()

compute a natural logarithm

max()

return the larger of two numbers

min()

return the smaller of two numbers

pow()

compute xy

random()

compute a random number; not available on all platforms

round()

round to the nearest integer

sin()

compute a sine

sqrt()

compute a square root

tan()

compute a tangent

## Description

Math is a read-only reference to a placeholder object that contains mathematical functions and constants. These functions and constants are conveniently grouped by this Math object, and are invoked with syntax like this:

```y = Math.sin(x); 