Prove that the limit of a constant number is that number. Show that \begin{equation} \lim_{x\to a}\,K=K \end{equation} where $K$ is a constant.

Problem: 

Prove that the limit of a constant number is that number. In other words, prove that
\begin{equation}
\lim_{x\to a}\,K=K
\end{equation}
where $K$ is a constant.

Answer: 

It is true that \begin{equation} \lim_{x\to a}\,K=K. \end{equation}