I find C# very well suited for doing math and all sorts of calculations, so here is an example. Just start a Console application and fill in the code. Have fun!
The code also shows a use of delegates and some Console functions.
If you don't know what the Newton-Raphson iteration method is, you can look it up here
There is much to be improved in my code:
Could have asked the user for input, instead of hardcoding some values.
Could have made a Forms app out of it.