What is the square root of 26?
You can only have an approximation: 5.09901951...
The square root of a number
Iterating this process gives you all the decimal digits you need.
If you want to calculate an approximation by hand, then I would recommend a form of Newton Raphson method, starting with first approximation
To iterate you can use the formula:
Personally, I like to deal with these approximations as rational approximations in the form
Stop when you think you have enough significant digits (typically about the number of significant digits of