Section Navigation

Precalculus: Mathematics for Calculus, 7th Edition

Published by Brooks Cole
ISBN 10: 1305071751
ISBN 13: 978-1-30507-175-9

Chapter 13 - Section 13.2 - Finding Limits Algebraically - 13.2 Exercises - Page 914: 44

Answer

(a) (i) $0$ (ii) $0$ (iii) $1$ (iv) $4$ (v) $6$ (vi) Does not exist. (b) See graph

Work Step by Step

(a) Based on the piece-wise function, we have: (i) For $x\to 0^+$, we should use the middle function, $\lim_{x\to 0^+}h(x)=\lim_{x\to 0^+}x^2=0^2=0$ (ii) For $x\to 0$, we need to test both left and right limits using the first and second equations respectively, $\lim_{x\to 0^-}h(x)=\lim_{x\to 0^-}x=0$, $\lim_{x\to 0^+}h(x)=\lim_{x\to 0^+}x^2=0$, thus $\lim_{x\to 0}h(x)=0$ (iii) For $x\to 1$, we should use the middle function, $\lim_{x\to 1}h(x)=\lim_{x\to 1}x^2=1$ (iv) For $x\to 2^-$, we should use the middle function, $\lim_{x\to 2^-}h(x)=\lim_{x\to 2^-}x^2=2^2=4$ (v) For $x\to 2^+$, we should use the third function, $\lim_{x\to 2^+}h(x)=\lim_{x\to 2^+}(8-x)=8-2=6$ (vi) For $x\to 2$, we need to test both left and right limits, since $\lim_{x\to 2^+}h(x)\ne \lim_{x\to 2^-}h(x)$ as shown above. $\lim_{x\to 2}h(x)$$ does not exist. (b) See graph.
Update this answer!

You can help us out by revising, improving and updating this answer.

Update this answer

After you claim an answer you’ll have 24 hours to send in a draft. An editor will review the submission and either publish your submission or provide feedback.