Thomas' Calculus 13th Edition

Published by Pearson
ISBN 10: 0-32187-896-5
ISBN 13: 978-0-32187-896-0

Chapter 11: Parametric Equations and Polar Coordinates - Section 11.7 - Conics in Polar Coordinates - Exercises 11.7 - Page 685: 4

Answer

$F(0,\pm\sqrt{2})$ Eccentricity$:\qquad e =\displaystyle \frac{\sqrt{2}}{2}$ Directrices$:\quad y=\pm 2\sqrt{2}$ Graph:

Work Step by Step

$2x^{2}+y^{2}=4\qquad/\div 4$ $\displaystyle \frac{x^{2}}{2}+\frac{y^{2}}{4}=1,\qquad a=2,b=\sqrt{2}$ The major axis is vertical. $c=\sqrt{a^{2}-b^{2}}=\sqrt{4-2}=\sqrt{2}$ $F(0,\pm\sqrt{2})$ Eccentricity$:\qquad e=\displaystyle \frac{c}{a}=\frac{\sqrt{2}}{2}$ Directrices$:\quad y=0\displaystyle \pm\frac{a}{e}$ $y=\displaystyle \pm\frac{2}{(\frac{\sqrt{2}}{2})}$ $y=\pm 2\sqrt{2}$
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.