Square Root Without InBuilt Functions Example Java Program

Definition

A square root of a number a is a number y such that y2 = a, in other words, a number y whose square (the result of multiplying the number by itself, or y * y) is a. For example, 4 and ?4 are square roots of 16 because 4^2 = (?4)^2 = 16.

Square Root Without InBuilt Functions Example Program

import java.util.Scanner;
public class SquareRootWithoutInBuilt{
    public static void main(String[] args){
	Scanner in=new Scanner(System.in);
	System.out.print("Enter the number for which Square root is to be found: ");
        double num =in.nextInt();
        squareRootMethod(num);
    }
    public static void squareRootMethod(double num){
        boolean checkpos = true;
        double numm;
        if(num==0){
            System.out.println("Square root of "+num+" = "+0);
        }
        else if(num<0){
            num=-num;
            checkpos = false;
        }
        double squareRoot = num/2;
        do{
            numm=squareRoot;
            squareRoot = (numm + (num/numm))/2;
        }while((numm-squareRoot)!=0);
        if(checkpos){
            System.out.println("Square roots of "+num+" are ");
            System.out.println("+"+squareRoot);
            System.out.println("-"+squareRoot);
        }
        else{
            System.out.println("Square roots of -"+num+" are ");
            System.out.println("+"+squareRoot+" i");
            System.out.println("-"+squareRoot+" i");
        }
    }
}

Sample Output

output is
Enter the number for which Square root is to be found: 2
Square roots of 2.0 are
+1.414213562373095
-1.414213562373095