Question

Show 3+ 2√5 is
irrational​

Answer 1

Answer:

Assume that 3+2√5 is rational.

Then,

3+2√5= a/b

√5=(a-3b)/2b

This gives that (a-3b)/2b is irrational but √5 is an irrational number, therefore, the assumption is wrong.

Hence, 3+2√5 is irrational.