# ASin()

Determines the arcsine of a number. The arcsine is the angle
whose sine is number.

```
ASin( number=number );
```

**Returns:** number

# Arguments

| Argument | Type | Required | Description | Default |
|----------|------|----------|-------------|---------|
| number | number | Yes | Sine of an angle. The value must be between -1 and 1, inclusive. |  |

# Examples

```cfml
sine = 1;
dump(Asin(sine)); // 1.570796326795 in radians
```







# Categories

[Numbers](../../categories/number.md), [Math](../../categories/math.md)

# See Also

[numeric.aSin()](../objects/numeric/asin.md)