Prove that 5-root3 is a irrational number.
Solution, let assuming that 5-root3 is a. rational numbers
so, 5-root3 =p/q (where p/q is a co-prime integer)
-root3 = p/q -5
root = p-5q/q
where root 3 is a irrational number so, contradiction arrisses due to wrong assumption