How do you find the square root of 730?

1 Answer
Sep 16, 2016

sqrt(730) ~~ 78813/2917 ~~ 27.01851217

Explanation:

730 = 2*5*73 has no square factors, so the square root cannot be simplified.

It is an irrational number a little greater than 27 = sqrt(729)

Since 730 = 27^2+1 is in the form n^2+1 it has a simple form of continued fraction:

sqrt(730) = [27;bar(54)] = 27+1/(54+1/(54+1/(54+1/(54+...))))

We can truncate this continued fraction early to get rational approximations for sqrt(730).

For example:

sqrt(730) ~~ [27;54] = 27+1/54 = 1459/54 = 27.0bar(185)

or more accurately:

sqrt(730) ~~ [27;54,54] = 27+1/(54+1/54) = 78813/2917 ~~ 27.01851217