C# / .NET - Math.Sqrt() method example

Math Sqrt is a static method that returns a number which is the square root of input value. The method works only on positive real numbers.

using System;

public class Program
{
    public static void Main(string[] args)
    {
        Console.WriteLine( Math.Sqrt(  4   ) ); //  2
        Console.WriteLine( Math.Sqrt(  9   ) ); //  3

        Console.WriteLine( Math.Sqrt(  2   ) ); //  1.4142135623730951
        Console.WriteLine( Math.Sqrt(  0.5 ) ); //  0.7071067811865476
        Console.WriteLine( Math.Sqrt(  0   ) ); //  0
        Console.WriteLine( Math.Sqrt( -1   ) ); //  NaN
    }
}

1. Documentation

namespace System
{
    public static class Math
    {
        // ...
        public static double Sqrt(double number) { ... }
        // ...
    }
}

2. Square root with Math.pow method examples

In this example, the way how to calculate square root using power function is presented. 

using System;

public class Program
{
    static double CalculateSqrt(double value)
    {
        return Math.Pow(value, 0.5);
    }

    public static void Main(string[] args)
    {
        // Examples:
        Console.WriteLine( CalculateSqrt(  4   ) ); //  2
        Console.WriteLine( CalculateSqrt(  9   ) ); //  3

        Console.WriteLine( CalculateSqrt(  2   ) ); //  1.4142135623730951
        Console.WriteLine( CalculateSqrt(  0.5 ) ); //  0.7071067811865476
        Console.WriteLine( CalculateSqrt(  0   ) ); //  0
        Console.WriteLine( CalculateSqrt( -1   ) ); //  NaN
    }
}