Returns the inverse cosine of the given number in radians.

**Sample Usage**

ACOS(0.5)

ACOS(C5)

**Syntax**

ACOS(number)

- number - The number for which the inverse cosine is to be computed.

**Examples**

ACOS(0.5) returns the inverse cosine of 0.5 in radians.

ACOS(C5) returns the inverse cosine of the number contained in C5.

**Notes**

- Use the DEGREES function to convert the result of ACOS into degrees. For example, DEGREES(ACOS(0.5)).
- The ACOS function returns a solution between 0 and Pi.