2.3a Lösning 5a

\[ \lim_{x \to 4}\, {x^2 - 16 \over x - 4} \, = \, \lim_{x \to 4}\, {(x + 4) \cdot {\color{Red} {(x-4)}} \over {\color{Red} {(x-4)}}} \, = \, \lim_{x \to 4}\, (x + 4) \, = \, 4 + 4 \, = \, 8 \]