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**ASIN(**//expression//**)**

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| **ASIN** | Returns inverse sine. |
| //expression// | A numeric constant, variable, or expression for the value of the sine. |

The **ASIN** procedure returns the inverse sine. The inverse of a sine is the angle that produces the sine. The return value is the angle in radians. p is a constant which represents the ratio of the circumference and radius of a circle. There are 2p radians (or 360 degrees) in a circle.

| **Return Data Type:** | REAL |

**Example:**

**PI        EQUATE(3.1415926535898)     !The value of PI**

**Rad2Deg   EQUATE(57.295779513082)     !Number of degrees in a radian**

**Deg2Rad   EQUATE(0.0174532925199)     !Number of radians in a degree**

** CODE**

** InvSine = ****ASIN****(SineAngle)            !Get the Arcsine**

**See Also:**

[[tan  return tangent .htm|TAN]]

[[atan  return arctangent .htm|ATAN]]

[[sin  return sine .htm|SIN]]

[[cos  return cosine .htm|COS]]

[[acos  return arccosine .htm|ACOS]]