MySQL ASIN() Function

The ASIN() function calculates the arc sine (inverse sine) of a given numeric value.


Syntax

ASIN(number)

Definition and Usage

  • The ASIN() function returns the arc sine of a number in radians.
  • The result is within the range [−π2,π2][- \frac{\pi}{2}, \frac{\pi}{2}] (-1.5708 to 1.5708 approximately).
  • The input value must be between -1 and 1. If the value is outside this range, the function returns NULL.

Parameter Values

Parameter Description
number Required. A numeric value between -1 and 1.

Technical Details

  • Works in: From MySQL 4.0

Examples

Example 1: Arc sine of a positive number

SELECT ASIN(0.25);

Result:

0.2526802551420786

Example 2: Arc sine of a negative number

SELECT ASIN(-0.8);

Result:

-0.9272952180016123

Example 3: Arc sine of 1

SELECT ASIN(1);

Result:

1.5707963267948966

Example 4: Arc sine of -1

SELECT ASIN(-1);

Result:

-1.5707963267948966

Example 5: Input outside the range

SELECT ASIN(1.5);

Result:

NULL

Usage Notes

  • Use the ASIN() function for trigonometric calculations or geometry problems requiring the inverse sine.
  • To convert radians to degrees, multiply the result by 180π\frac{180}{\pi}:
    SELECT ASIN(0.25) * (180 / PI());
    

Result in degrees:

14.47751218592992

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