Calculus: Early Transcendentals 9th Edition

Published by Cengage Learning
ISBN 10: 1337613924
ISBN 13: 978-1-33761-392-7

Chapter 3 - Section 3.2 - The Product and Quotient Rules - 3.2 Exercises - Page 189: 4

Answer

$\frac{{dy}}{{dx}} = - 40{x^3} - 21{x^2} + 44x + 14$

Work Step by Step

$$\eqalign{ & y = \left( {10{x^2} + 7x - 2} \right)\left( {2 - {x^2}} \right) \cr & {\text{Differentiating}} \cr & \frac{{dy}}{{dx}} = \frac{d}{{dx}}\left[ {\left( {10{x^2} + 7x - 2} \right)\left( {2 - {x^2}} \right)} \right] \cr & {\text{Differentiate by using the formula }}\left( {fg} \right)' = fg' + gf' \cr & {\text{Let }}f = \left( {10{x^2} + 7x - 2} \right){\text{ and }}g = \left( {2 - {x^2}} \right) \cr & {\text{Therefore}}{\text{,}} \cr & \frac{{dy}}{{dx}} = \left( {10{x^2} + 7x - 2} \right)\left( {2 - {x^2}} \right)' + \left( {2 - {x^2}} \right)\left( {10{x^2} + 7x - 2} \right)' \cr & {\text{Compute derivatives}} \cr & \frac{{dy}}{{dx}} = \left( {10{x^2} + 7x - 2} \right)\left( { - 2x} \right) + \left( {2 - {x^2}} \right)\left( {20x + 7} \right) \cr & {\text{Use the distributive property}} \cr & \frac{{dy}}{{dx}} = - 20{x^3} - 14{x^2} + 4x + 40x + 14 - 20{x^3} - 7{x^2} \cr & {\text{Simplify}} \cr & \frac{{dy}}{{dx}} = - 40{x^3} - 21{x^2} + 44x + 14 \cr} $$
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.