Question 51026
first factorize

78:2=39
39:3=13
13:13=1


so we got 2, 3 and 13 factors. if you don't have all the factors with even powers you can not find the exact value of their square root. so let it stay {{{sqrt(78)}}} or {{{sqrt(2)*sqrt(3)*sqrt(13)}}} because there is no way to simplify it.


that's way people call the numbers like {{{sqrt(78)}}} irrational numbers because it is impossible to find an answer as a fraction or an integer.