This is the first thing you should always try: just plug the value of x into f(x). If you obtain a number (and in particular, if you don’t get $\dfrac{0}{0}$), you have your answer and are finished. In that case, these problems are completely straightforward.
Example.
Find $\displaystyle{\lim_{x \to 2}(x^3-5x + 7)}$.
Solution.
\begin{align*} \lim_{x \to 2}(x^3-5x + 7) &= (2)^3 -5(2) + 7 \\ &= 8 -10 + 7 = 5 \quad \cmark \end{align*}
Practice this (simple!) tactic in the next few problems. The solutions are immediately available using the Show/Hide Solution toggle. #5 illustrates an important point.
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