Related Functions:

- ACOS Function
- ATAN Function
- SIN Function

The ASIN function Returns the arcsine, or inverse sine, of a number. The arcsine is the angle whose sine is number. The returned angle is given in radians in the range to .

### Syntax

=ASIN(number)

#### Arguments

Argument | Description |
---|---|

number | The sine of the angle you want and must be from -1 to 1 |

#### Examples

A | B | C | |
---|---|---|---|

1 | Formula | Result | Notes |

2 | =ASIN(-0.5) | -0.523598776 | Arcsine of -0.5 in radians, – |

3 | =ASIN(-0.5)*180/PI() | -30 | Arcsine of -0.5 in degrees |

4 | =ASIN(1/SQRT(2)) | 0.785398163 | Arcsine of in radians |

5 | =DEGREES(ASIN(1/SQRT(2))) | 45 | Arcsine of in degrees |

Note: If you want the angle returned by the ASIN function to be expressed in degrees, you can convert it, using the DEGREES function: =DEGREES(radians)

#### Common Function Error(s)

Problem | What went wrong |
---|---|

#VALUE! | Occurs if the supplied number argument is not recognized as a numeric value |

#NUM! | Occurs if the supplied number argument is not in the range -1 to +1 |

The arcsine is the inverse of sine. Therefore, for the simple right-angle triangle at right, the arcsine of the opposite side (a), divided by the hypotenuse (h), is equal to angle A, i.e. for the triangle at right, the arcsine for angle B is calculated as:

See Wikipedia for more information on Inverse Trigonometric Functions.