Calculus: Early Transcendentals (2nd Edition)

Published by Pearson
ISBN 10: 0321947347
ISBN 13: 978-0-32194-734-5

Chapter 7 - Integration Techniques - Review Exercises - Page 593: 22

Answer

$$3\ln \left| {x + 1} \right| + \ln \left| {2x + 1} \right| + C$$

Work Step by Step

$$\eqalign{ & \int {\frac{{8x + 5}}{{2{x^2} + 3x + 1}}} dx \cr & = \int {\frac{{8x + 5}}{{\left( {x + 1} \right)\left( {2x + 1} \right)}}} dx \cr & {\text{partial fractions}} \cr & \frac{{8x + 5}}{{\left( {x + 1} \right)\left( {2x + 1} \right)}} = \frac{A}{{x + 1}} + \frac{B}{{2x + 1}} \cr & {\text{multiplying}} \cr & 8x + 5 = A\left( {2x + 1} \right) + B\left( {x + 1} \right) \cr & x = - 1 \to A = 3 \cr & x = - \frac{1}{2} \to B = 2 \cr & {\text{substituting constants}} \cr & \frac{A}{{x + 1}} + \frac{B}{{2x + 1}} = \frac{3}{{x + 1}} + \frac{2}{{2x + 1}} \cr & \int {\frac{{8x + 5}}{{2{x^2} + 3x + 1}}} dx = \int {\left( {\frac{3}{{x + 1}} + \frac{2}{{2x + 1}}} \right)dx} \cr & {\text{integrating}} \cr & = 3\ln \left| {x + 1} \right| + \ln \left| {2x + 1} \right| + C \cr} $$
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.