Question

(2.) please solve it i can't understand this question please solve it.......

Answer 1

let us suppose 3+2root5 is rational
then 3+root5=a/b where a and b are some integers
2root5=a/b-3
root 5=1/2(a/b-3)
here 1/2(a/b-3) is rational.But it is contradictory the fact that root 5is irrational