$$ a,b \in \mathbb{Q} $$ $$ \sqrt{a} \notin \mathbb{Q} ~\text{and}~ \sqrt{b} \notin \mathbb{Q} \implies \sqrt{a} + \sqrt{b} \notin \mathbb{Q} $$
I'm not really sure on how to solve this, however, I know it's true, it's an implication of a theorem, how can I prove this directly?
