Calculus, 10th Edition (Anton)

Published by Wiley
ISBN 10: 0-47064-772-8
ISBN 13: 978-0-47064-772-1

Chapter 1 - Limits and Continuity - 1.5 Continuity - Exercises Set 1.5 - Page 99: 16

Answer

$${\text{Continuous everywhere}}{\text{.}}$$

Work Step by Step

$$\eqalign{ & {\text{Let the function }}f\left( x \right) = \frac{{2x + 1}}{{4{x^2} + 4x + 5}} \cr & {\text{This is a rational function}}{\text{, and a rational function is continuous }} \cr & {\text{at every point where the denominator is nonzero}}{\text{, and has }} \cr & {\text{discontinuities at the points where the denominator is zero}}{\text{.}} \cr & {\text{Setting the denominator to 0}} \cr & \,\,\,\,\,\,\,\,\,\,\,\,\,\,\,\,\,\,\,\,\,\,\,\,\,\,\,\,\,\,\,\,\,\,\,\,\,\,\,\,\,\,\,\,\,4{x^2} + 4x + 5 = 0 \cr & {\text{Solving the equation by the quadratic formula}} \cr & \,\,\,\,\,\,\,\,\,\,\,\,\,\,\,\,\,\,\,\,\,\,\,\,\,\,\,\,\,\,\,\,\,\,\,\,\,\,\,\,\,\,\,\,x = \frac{{ - \left( { - 4} \right) \pm \sqrt {{{\left( 4 \right)}^2} - 4\left( 4 \right)\left( 5 \right)} }}{{2\left( 4 \right)}} \cr & \,\,\,\,\,\,\,\,\,\,\,\,\,\,\,\,\,\,\,\,\,\,\,\,\,\,\,\,\,\,\,\,\,\,\,\,\,\,\,\,\,\,\,\,x = \frac{{4 \pm \sqrt { - 64} }}{8} \cr & {\text{Thus}}{\text{, there are no real values at which the denominator is zero}} \cr & {\text{then}}{\text{, the function is continuous for all real numbers}}{\text{.}} \cr & \cr & {\text{Continuous everywhere}}{\text{.}} \cr} $$
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.