Thomas' Calculus 13th Edition

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

Chapter 9: First-Order Differential Equations - Section 9.3 - Applications - Exercises 9.3 - Page 544: 11

Answer

$-1$ The equations $2x^2 +3y^2=5$ and $y^2=x^3$ are perpendicular to each other at the point $(1,1)$.

Work Step by Step

We have $2x^2 +3y^2=5$ and $y^2=x^3$ So, $2x^2 +3(x^3) =5$ and $y^2=x^3=(1)^3 =1$ Now, we will find the slope of equation $2x^2 +3y^2=5$. $4x+6y \dfrac{dy}{dt}=0 \implies \dfrac{dy}{dt} =\dfrac{-2x}{3y}$ and $m_1=\dfrac{dy}{dt}(1,1) =\dfrac{-2(1)}{3(1)}=\dfrac{-2}{3}$ and $m_2=\dfrac{dy}{dt}]= \dfrac{3x^2}{2y} \implies \dfrac{dy}{dt}(1,1)= \dfrac{3}{2}$ Now, $m_1 \times m_2= \dfrac{-2}{3} \times \dfrac{3}{2} =-1$ This implies that the equations $2x^2 +3y^2=5$ and $y^2=x^3$ are perpendicular to each other at the point $(1,1)$.
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.