# Definition:Removable Discontinuity of Real Function/Definition 1

## Definition

Let $A \subseteq \R$ be a subset of the real numbers.

Let $f: A \to \R$ be a real function.

Let $f$ be discontinuous at $a\in A$.

The point $a$ is a removable discontinuity of $f$ if and only if the limit $\displaystyle \lim_{x \mathop \to a} \map f x$ exists.