Easiest method to find square root of N is to take make a good an approximation (X) as possible. Then do this calculation:
((N/X) +X)/2 <----- call this answer A.
For further accuracy repeat the process but use the
formula:
((N/A)+A)/2 <-------- The answer should be the square root of N accurate to a few decimal places.
Sounds complicated? Try this for square root of 40 (for which answer is 4.472)
Start with estimate of 4
((20/4)+4)/2=4.5
((20/4.5)+4.5)/2= 4.472
the rule can be described as divide your number by your estimate, add your estimate, then divide by 2.