Question

Find any two irrational numbers between 3 and 3.5.

Answer 1

Irrational numbers are non terminating and non recurring 
so the irrational numbers are 3.101001000100001..........
and 3.25648871235489.................... 

you can have more numbers 

Answer 2

$\sqrt{10} and \sqrt{11}$. Are the two irrational numbers between 3 and 3.5. There are infinite possibilities. These are two of them.