C++ Math cos

The function is used to find the cosine of an angle expressed in terms of radian.

Syntax

Consider a radian 'x'. Syntax would be:

float cos(float x);
float cos(double x);
float cos(long double x);
double cos(integral x);

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

Parameter

x : Value specified in terms of radian.

Return value

It returns the cosine of an angle in the range of[-1,1].

Example 1

Let's see a simple example when the value of x is positive.

#include <iostream>
#include<math.h>
using namespace std;
int main()
{
    double degree=60;
    double d=60*3.14/180;
    cout<<"Cosine of an angle is : "<<cos(d);
    return 0;
}

Output:

Cosine of an angle is : 0.50046

In this example, cos function calculates the cosine of an angle when the degree is equal to 60.

Example 2

Let's see a simple example when the value of x is negative.

#include <iostream>
#include<math.h>
using namespace std;
int main()
{
  double degree= -90;
  double radian=degree*3.14/180;
  cout<<"Cosine of an angle is :"<<cos(radian);
  return 0;
}

Output:

Cosine of an angle is :0.000796327

In this example, cos function finds the cosine of an angle when the value is negative but it remains the same as cos(-x) =cos(x).