ACOS

Syntax

ACOS (Data)

Description

The ACOS function returns the arc-cosine of Data. The result is the angle (in radians) whose cosine equals Data.

The value of Data must fall between 1 and 1; otherwise, ACOS returns an error value.

To convert from radians to degrees, multiply by 180 / PI( ). (The PI function returns the value of PI.)

Returns

The arc-cosine of Data.

Example

The following examples employ the ACOS built-in function:

• ACOS(0.5) returns 1.0471975512 (angle in radians).

• ACOS(0.5) * 180 / PI( ) returns 60 (angle in degrees).

• ACOS(SQRT(2) / 2) returns 0.7853981634 (angle in radians).

• ACOS(SQRT(2) / 2) * 180 / PI( ) returns 45 (angle in degrees).