C++ Math acos()

This function computes the inverse cosine of a number in radian.

Syntax

Suppose a number is x. Syntax would be:

Note: If the value passed is an integer type, then it is cast to double.

Parameter

x: The value whose arc cosine is to be calculated. It should be in the range[-1,1].

Return value

Example 1

Let's see the simple example when the value of x is greater than 1.

Output:

Value of cosine is :0.000796274
Inverse of cosine is :nan   

In this example, acos() function calculates the inverse cosine of a number when the value of x is greater than 1.

Example 2

Let's see the simple example when the value of x is equal to zero.

Output:

Value of cosine is :1
Inverse of cosine is :1.5708   

In this example, acos() function calculates the inverse cosine of a number when the value of x is equal to zero.

Example 3

Let's see the simple example when the value x is less than -1.

Output:

Value of cosine is :0.50046
Inverse of cosine is :nan   

In this example, acos() function calculates the inverse cosine of a number when the value of x is less than -1.