Derivatives · Exercise 137

Use technology to evaluate the limit.

Evaluate the limit by hand.
$\begin{array}{c}lim\\ {}^{x\to 1}\end{array}f\left(x\right),\text{where}f\left(x\right)=\{\begin{array}{cc}4x-7& x\ne 1\\ x^2-4& x=1\end{array}$
At what value(s) of $x$ is the function below discontinuous?
$f\left(x\right)=\{\begin{array}{c}4x-7x\ne 1\\ x^2-4x=1\end{array}$

OpenStax, Precalculus 2e · §12.4 Derivatives · Exercise 137