The ASIN function, also called arc-sine, returns the inverse sine of a value. The input number must be between -1 and 1, inclusive. Geometrically, given the ratio of a triangle’s opposite side over its hypotenuse, the function returns the angle of the triangle. For example, given a ratio of 0.5 the function returns the angle of 0.524 radians.

**Syntax**: =ASIN(number)

The ASIN function syntax has the following arguments:

**number**– The value to get the inverse sine of. The number must be between -1 and 1 inclusive.

**Example**: Let’s look at some Excel ASIN function examples and explore how to use the ASIN function as a worksheet function in Microsoft Excel:

**Syntax**: =ASIN(A2)

**Result**:

Based on the Excel spreadsheet above, the following ASIN examples would return:

**Syntax**: =ASIN(A3)**Result**: -0.523598776

**Syntax**: =ASIN(A4)**Result**: -0.747762635

**Syntax**: =ASIN(A5)**Result**: 0

**Syntax**: =ASIN(A6)**Result**: 0.747762635

**Syntax**: =ASIN(A7)**Result**: 0.523598776

**Syntax**: =ASIN(A8)**Result**: 1.570796327