## Calculus (3rd Edition)

Published by W. H. Freeman

# Chapter 2 - Limits - 2.2 Limits: A Numerical and Graphical Approach - Exercises - Page 54: 9

#### Answer

See the proof below.

#### Work Step by Step

We have $$|3 x-12|=3|x-4|$$ Since $|3x-12|$ is a multiple of $|x-4|$, then we see that $|3x-12|$ is small by taking $x$ sufficiently close to $4$. Hence, we have $$\lim _{x \rightarrow 4} 3x=12.$$

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