Java - Math cos(double) method

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Description

The Java Math cos(double a) returns the trigonometric cosine of an angle.If the argument is NaN or an infinity, then the result is NaN. The computed result must be within 1 ulp of the exact result. Results must be semi-monotonic.

Declaration

Following is the declaration for java.lang.Math.cos() method

public static double cos(double a)

Parameters

a − the value whose trigonometric cosine is to be returned.

Return Value

This method returns the trigonometric cosine of the argument.

Exception

NA

Example 1

The following example shows the usage of Math cos() method.

package com.tutorialspoint;
public class MathDemo {
   public static void main(String[] args) {

      // get a variable x which is equal to PI/2
      double x = Math.PI / 2;

      // convert x to radians
      x = Math.toRadians(x);

      // get the arc sine of x
      System.out.println("Math.cos(" + x + ")=" + Math.cos(x));
   }
}

Output

Let us compile and run the above program, this will produce the following result −

Math.cos(0.027415567780803774)=0.9996242168594817

Example 2

The following example shows the usage of Math cos() method of 0° angle.

package com.tutorialspoint;
public class MathDemo {
   public static void main(String[] args) {

      // get a variable x which is equal to zero
      double x = 0.0d;

      // convert x to radians
      x = Math.toRadians(x);

      // get the arc sine of x
      System.out.println("Math.cos(" + x + ")=" + Math.cos(x));
   }
}

Output

Let us compile and run the above program, this will produce the following result −

Math.cos(0.0)=1.0

Example 3

The following example shows the usage of Math cos() method of 45° angle.

package com.tutorialspoint;
public class MathDemo {
   public static void main(String[] args) {

      // get a variable x which is equal to zero
      double x = 45.0d;

      // convert x to radians
      x = Math.toRadians(x);

      // get the arc sine of x
      System.out.println("Math.cos(" + x + ")=" + Math.cos(x));
   }
}

Output

Let us compile and run the above program, this will produce the following result −

Math.cos(0.7853981633974483)=0.7071067811865476