The functionality of java.lang.Math class is to perform basic operations such as addition, subtraction, square root, logarithmic and trigonometric functions. Following is the syntax declaration of this class. [java] public final class Math extends Object [/java] Following are the basic methods of java.lang.Math class.

DemoMath.java [java] package com.SPlessons; import java.lang.Math; public class DemoMath { public static void main(String[] args) { // get some doubles to find their absolute values double a = 1234.1874d; double b = -0123.0d; // get and print their absolute values System.out.println("Math.abs(" + a + ")=" + Math.abs(a)); System.out.println("Math.abs(" + b + ")=" + Math.abs(b)); System.out.println("Math.abs(-9999.555d)=" + Math.abs(-5555.666d)); } } [/java] The functionality of this method is to return absolute value. Here if the value is zero( either negative or positive) then it returns positive zero. Output: Following is the result will be generated. [java] Math.abs(1234.1874)=1234.1874 Math.abs(-123.0)=123.0 Math.abs(-9999.555d)=5555.666 [/java] DemoMath.java [java] package com.SPlessons; import java.lang.Math; public class DemoMath { public static void main(String[] args) { // get a variable d which is equal to PI/2 double d = Math.PI / 2; // convert d to radians d = Math.toRadians(d); // get the arc cosine of x System.out.println("Math.acos(" + d + ") = " + Math.acos(d)); } } [/java] Here if the value is NaN(Not a Number) then the result is NaN, here the purpose of java.lang.Math.toRadians is to change over a point measured in degrees to a roughly proportional edge measured in radians. Output: The result will be as follows. [java] Math.acos(0.027415567780803774) = 1.5433773235341761 [/java] DemoMath.java [java] package com.SPlessons; import java.lang.Math; public class DemoMath { public static void main(String[] args) { // get two double numbers double m = 265.9; double n = 0.5878; // call ceal for these these numbers System.out.println("Math.ceil(" + m + ")=" + Math.ceil(m)); System.out.println("Math.ceil(" + n + ")=" + Math.ceil(n)); System.out.println("Math.ceil(-0.65)=" + Math.ceil(-0.95)); } } [/java] In case the argument value is same as integer value then result will be as argument value only. Output: The result will be as follows. [java] Math.ceil(265.9)=266.0 Math.ceil(0.5878)=1.0 Math.ceil(-0.65)=-0.0 [/java] Instead of the ceil place the floor in the same code then result will be as follows. Output: The functionality of floor() method is that to return the greatest double value. [java] Math.ceil(265.9)=265.0 Math.ceil(0.5878)=0.0 Math.ceil(-0.65)=-1.0 [/java] DemoMath.java [java] package com.SPlessons; import java.lang.Math; public class DemoMath { public static void main(String[] args) { // get two double numbers numbers double m = 16; double n = 144; // print the square root of these doubles System.out.println("Math.sqrt(" + m + ")=" + Math.sqrt(m)); System.out.println("Math.sqrt(" + n + ")=" + Math.sqrt(n)); } } [/java] Here if the argument is negative or positive then the result will be same as the argument. If the argument is less than zero then result will be NaN(Not a Number). Output: The result will be as follows. [java] Math.sqrt(16.0)=4.0 Math.sqrt(144.0)=12.0 [/java]

• The cos(double a) method is used to return the trigonometric cosine of an angle.
• The java.lang.Math class also will hire the methods from java.lang.Object class.
• The value of one radian equals to 57.2958 degrees.