Question 320018
Simplest form of a radical has no radicals in the denominator (the bottom part of a fraction0.  The radicand (what's inside that square root sign - what you are finding the square root of) can have no decimals or fractions. 

To simplify a radical:
Reduce powers 
Rationalize denominators

To rationalize a monomial denominator, multiply the numerator and denominator by the radical
(√5)/(√3)   so multiply by √3/√3 to get (√15)/3

If you have a monomial denominator such as 4 + √8 multiply by the conjugate 4 - √8. Foil to get 16 - 4√8  + 4√8 - 8 which is just 8.