It is not the answer for the question. "Find a non-context-free language A on Σ" the answer is not on specified Σ. And there isn't any proof on your answer. also you need to prove
A ∪ B is context-free
You did not said anything about context freenes, you are defining regular and non regular languages.
It is not the answer for the question. "Find a non-context-free language A on Σ" the answer is not on specified Σ. And there isn't any proof on your answer. also you need to prove
A ∪ B is context-free
You did not said anything about context freenes, you are defining regular and non regular languages.