How do you simplify sqrt1919?

1 Answer
May 16, 2016

sqrt(19)19 is already in simplest form.

Explanation:

1919 is a prime number, so has no square factors.

As a result it is not possible to simplify sqrt(19)19, the positive irrational number whose square is 1919.

sqrt(19) ~~ 4.35889894354194.35889894354

The continued fraction expansion of sqrt(19)19 looks like this:

sqrt(19) = [4; bar(2, 1, 3, 1, 2, 8)] = 4+1/(2+1/(1+1/(3+1/(1+1/(2+1/(8+1/(2+1/(1+...))))))))

We can get an economical rational approximation for sqrt(19) by truncating just before the end of the repeating part:

sqrt(19) ~~ [4; 2, 1, 3, 1, 2] = 4+1/(2+1/(1+1/(3+1/(1+1/2)))) = 170/39 = 4.bar(358974)