Calculate arc cosine of a value in R programming – acos() function

The ** acos()** is an inbuilt function in R Programming which is used to calculate arc cosine of the specified radian value and output is also in radians.

Syntax:`acos(radian)`

Return:Returns the arc cosine value of radian.

**Example 1:**

`# Using acos() method` `gfg <` `-` `acos(pi` `/` `4` `)` ` ` `print` `(gfg)` |

**Output:**

[1] 0.7853982

**Example 2:**

`# Using acos() method` `gfg <` `-` `acos(pi` `/` `6` `)` ` ` `print` `(gfg)` |

**Output:**

[1] 1.019727