New posts in Rationality Testing

How to show that the product of two irrational numbers may be irrational?

If $P$ and $Q$ are distinct primes, how to prove that $\sqrt{PQ}$ is irrational?

Prove that 2.101001000100001... is an irrational number.

Can $\sqrt{n} + \sqrt{m}$ be rational if neither $n,m$ are perfect squares?

Prove that $\sqrt 2 + \sqrt 3$ is irrational

Prove that $\sqrt 5$ is irrational

Critiques on proof showing $\sqrt{12}$ is irrational.

Is the sum and difference of two irrationals always irrational?

Proving $\sqrt 3$ is irrational.

$\sin 1^\circ$ is irrational but how do I prove it in a slick way? And $\tan(1^\circ)$ is .....