# Use the while statement to implement Newton's method for finding the square root : double Calculation « Data Type « C# / CSharp Tutorial

```using System;

public class MainClass {
public static void Main( ) {
double epsilon   = 1.0e-9;
double guess    = 11.0;

double value = 2;

double result = ((value / guess) + guess) / 2;

Console.WriteLine( "Guess Value  = {0}", guess  );
Console.WriteLine( "Result Value = {0}", result );

while( Math.Abs(result - guess) > epsilon ) {
guess = result;
result = ((value / guess) + guess) / 2;
Console.WriteLine( "Guess Value  = {0}", guess  );
Console.WriteLine( "Result Value = {0}", result );
}

Console.WriteLine("The approx sqrt of {0} is {1}", value, result );
}
}
```
```Guess Value  = 11
Result Value = 5.59090909090909
Guess Value  = 5.59090909090909
Result Value = 2.97431633407243
Guess Value  = 2.97431633407243
Result Value = 1.82336988350512
Guess Value  = 1.82336988350512
Result Value = 1.46012001740362
Guess Value  = 1.46012001740362
Result Value = 1.41493521627426
Guess Value  = 1.41493521627426
Result Value = 1.41421374640426
Guess Value  = 1.41421374640426
Result Value = 1.41421356237311
Guess Value  = 1.41421356237311
Result Value = 1.41421356237309
The approx sqrt of 2 is 1.41421356237309```
 2.27.double Calculation 2.27.1. Implement the Pythagorean Theorem 2.27.2. doubles and arithmetic operators 2.27.3. Compute the area of a circle with 'double' 2.27.4. Calculate the radius of a circle given its area using Math function 2.27.5. Use the while statement to implement Newton's method for finding the square root 2.27.6. Do calculation with double value 2.27.7. double base Fahrenheit and Celsius (Centigrade) Scales 2.27.8. Returns the variable Area as a double value.