Problem: Write a Java program that calculates and displays the square root of a number using the Math.sqrt() method.

Solution

Here’s my solution based on the original challenge:

//import static java.lang.Math.sqrt;

public class Main {
    public static void main(String[] args){
        double myNumber = 9;
        double result = Math.sqrt(myNumber);
        System.out.println(result);
    }
}

//You can use Math.sqrt() to find the square root of a number:

Output:

3.0

Explanation

Mathematical Concept:

The square root of a number ( x ) is a value ( y ) such that ( y^2 = x ). In Java, we can use the Math.sqrt() method to compute the square root.

For example: √9 = 3 because 3 × 3 = 9

Program Flow:

  1. Declare Variable: Store the number (9) in myNumber
  2. Calculate: Use Math.sqrt() to find the square root
  3. Store Result: Save the calculated value in result
  4. Display: Print the result directly

Key Points:

  • Math.sqrt(): Built-in Java method for square root calculations
  • Double Data Type: Handles decimal results accurately
  • Direct Output: Simple println() displays the numerical result
  • Static Import: The commented line shows alternative import syntax

Key Concepts Used

  • Math Class: Accessing mathematical functions in Java
  • Method Call: Using Math.sqrt() with a parameter
  • Variable Assignment: Storing calculation results
  • Data Types: Working with double for precision

Enhanced Versions

With User Input:

import java.util.Scanner;

public class Main {
    public static void main(String[] args) {
        Scanner scanner = new Scanner(System.in);

        System.out.print("Enter a number: ");
        double myNumber = scanner.nextDouble();
        double result = Math.sqrt(myNumber);
        System.out.println("The square root of " + myNumber + " is " + result);

        scanner.close();
    }
}

With Input Validation:

import java.util.Scanner;

public class Main {
    public static void main(String[] args) {
        Scanner scanner = new Scanner(System.in);

        System.out.print("Enter a positive number: ");
        double myNumber = scanner.nextDouble();

        if (myNumber >= 0) {
            double result = Math.sqrt(myNumber);
            System.out.printf("√%.2f = %.2f%n", myNumber, result);
        } else {
            System.out.println("Error: Cannot calculate square root of negative numbers!");
        }

        scanner.close();
    }
}

Multiple Calculations:

public class SquareRootCalculator {
    public static void main(String[] args) {
        double[] numbers = {4, 9, 16, 25, 36};

        System.out.println("Square Root Calculations:");
        System.out.println("Number\t√Number");
        System.out.println("---------------");

        for (double num : numbers) {
            double result = Math.sqrt(num);
            System.out.printf("%.0f\t%.1f%n", num, result);
        }
    }
}

Once you master square root, explore these Math class methods:

  • Math.pow(x, y): Calculate x raised to power y
  • Math.cbrt(x): Calculate cube root
  • Math.abs(x): Get absolute value
  • Math.round(x): Round to nearest integer
  • Math.ceil(x): Round up
  • Math.floor(x): Round down

Real-World Applications

  • Engineering: Calculating distances and dimensions
  • Physics: Working with formulas involving square roots
  • Statistics: Computing standard deviation
  • Graphics: Distance calculations in 2D/3D space
  • Finance: Risk calculations and statistical analysis

What I Learned

  • The Math.sqrt() method is the standard way to calculate square roots
  • double data type is essential for mathematical calculations
  • Java’s Math class provides many useful mathematical functions
  • Simple variable assignment makes code readable
  • Direct output is effective for basic calculations

📁 This code can be found at: BlogCode Repository

Happy hacking! 🎯