# Interior of union of two sets with empty interior

Let $X$ and $Y$ be subsets of $\mathbb{R}^n$. If $\text{int}(X)$ and $\text{int}(Y)$ are empty sets and $X$ is closed, then $\text{int}(X \cup Y)$ is an empty set.

Mona Vinci

39

## Answer

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Erdos

4.7K

The answer is accepted.

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