Question

2√5/5 prove that it is irrational

Answer 1

Here 2√5 is irrational and 5 is rational .so dividing irrational with rational is always irrational.
Thus 2√5is irrational..

Answer 2

Numbers in root always irrational but root 4 it is not because it answer is 2. those numbers which have their root are rational. root5 is not the root of any number so it is irrational