/*! This file is auto-generated */ .wp-block-button__link{color:#fff;background-color:#32373c;border-radius:9999px;box-shadow:none;text-decoration:none;padding:calc(.667em + 2px) calc(1.333em + 2px);font-size:1.125em}.wp-block-file__button{background:#32373c;color:#fff;text-decoration:none} Problem 13 Find the value of \(K\) such tha... [FREE SOLUTION] | 91Ó°ÊÓ

91Ó°ÊÓ

Find the value of \(K\) such that the parabolas \(y=c_{1} x^{2}+K\) are the orthogonal trajectories of the family of ellipses \(x^{2}+2 y^{2}-y=c_{2}\).

Short Answer

Expert verified
The value of $K$ such that the parabolas \(y = c_{1}x^2 + K\) are the orthogonal trajectories of the family of ellipses \(x^2 + 2y^2 - y = c_{2}\) is \(K = \frac{1}{4}\).

Step by step solution

01

Find the slope of the tangent to the ellipse

To find the slope of the tangent, we will differentiate the equation of the ellipse with respect to x. Given, \(x^2 + 2y^2 - y = c_{2}\). Differentiating both sides with respect to x: \[2x + 4y\frac{dy}{dx} - \frac{dy}{dx} = 0\] Now, solve for \(\frac{dy}{dx}\): \[\frac{dy}{dx}(4y - 1) = -2x\] \[\frac{dy}{dx} = \frac{-2x}{4y - 1}\]
02

Find the slope of the tangent to the parabola

To find the slope of the tangent to the parabola, we will differentiate the equation of the parabola with respect to x. Given, \(y = c_{1}x^2 + K\). Differentiating both sides with respect to x: \[\frac{dy}{dx} = 2c_{1}x\]
03

Check the condition for orthogonality

For two curves to be orthogonal, the product of the slopes should be equal to -1: \[\frac{-2x}{4y - 1} \cdot 2c_{1}x = -1\] \[4c_{1}x^2 = 4y - 1\] Now substitute the equation of the parabola, \(y = c_{1}x^2 + K\), into the equation: \[4c_{1}x^2 = 4(c_{1}x^2 + K) - 1\]
04

Solve for K

Now solve the equation for K: \[0 = 4K - 1\] \[K = \frac{1}{4}\] Therefore, the value of K is \(\frac{1}{4}\) for the parabolas to be the orthogonal trajectories of the given family of ellipses.

Unlock Step-by-Step Solutions & Ace Your Exams!

  • Full Textbook Solutions

    Get detailed explanations and key concepts

  • Unlimited Al creation

    Al flashcards, explanations, exams and more...

  • Ads-free access

    To over 500 millions flashcards

  • Money-back guarantee

    We refund you if you fail your exam.

Over 30 million students worldwide already upgrade their learning with 91Ó°ÊÓ!

Key Concepts

These are the key concepts you need to understand to accurately answer the question.

Differential Equations
Differential equations are mathematical tools used to describe the relationship between a function and its derivatives. These equations are central in mathematics, physics, engineering, and many other fields, as they model the behavior of dynamic systems.

For instance, in our exercise, we have the equation of an ellipse and a parabola. A differential equation is formulated by differentiating these equations with respect to one variable to find the slope of the tangent at any point on these curves. Specifically, the slope is represented by \( \frac{dy}{dx} \) which is the derivative of the function \( y \) with respect to \( x \). Understanding how to manipulate and solve these equations is crucial for finding the desired solution, such as the value of \( K \) for the orthogonal trajectories of the given curves.
Slope of Tangent
The slope of a tangent linearly approximates a curve at a specific point and is a fundamental concept in calculus. It is essentially the rate of change or derivative at that point. By calculating the slope, we get an insight into how the function behaves near that point.

In the context of orthogonal trajectories, the slopes of tangents are particularly important because they determine the criterion for orthogonality - when the product of their slopes is -1. This means that the tangent lines drawn at the intersection points of the two curves are perpendicular to each other. For our exercise, the step-by-step solution shows how to find the slopes of the elliptical and parabolic families and then uses the orthogonality condition to solve for the constant \( K \).
Differentiation
Differentiation is the process of finding the derivative of a function, which represents the rate at which a function is changing at any given point. In simpler terms, it tells us how a quantity y changes with respect to another quantity x.

To find the value of \( K \) in our exercise, we differentiate the equations of the ellipse and parabola to find their slopes. This process is essential in order to apply the orthogonality condition for their slopes. In the problem, the differentiation of the parabola yields a straightforward linear derivative, while the ellipse, being implicitly defined in terms of \( x \) and \( y \) yields a derivative that requires solving for \( \frac{dy}{dx} \) to find the slope. Understanding differentiation is not just about applying formulas, but also about comprehending the relationship between the physical or geometric representation of functions and their algebraic expressions.

One App. One Place for Learning.

All the tools & learning materials you need for study success - in one app.

Get started for free

Most popular questions from this chapter

Exactly one person in an isolated island population of 10,000 people comes down with a certain disease on a certain day. Suppose the rate at which this disease spreads is proportional to the product of the number of people who have the disease and the number of people who do not yet have it. If 50 people have the disease after 5 days, how many have it after 10 days?

A large tank initially contains 200 gal of brine in which 15 lb of salt is dissolved. Starting at \(t=0\), brine containing 4 lb of salt per gallon flows into the tank at the rate of \(3.5 \mathrm{gal} / \mathrm{min} .\) The mixture is kept uniform by stirring and the well-stirred mixture leaves the tank at the rate of \(4 \mathrm{gal} / \mathrm{min}\). (a) How much salt is in the tank at the end of one hour? (b) How much salt is in the tank when the tank contains only 50 gal of brine?

The human population of a certain island satisfies the logistic law \((3.58)\) with \(k=0.03, \lambda=3(10)^{-8}\), and time \(t\) measured in years. (a) If the population in 1980 is 200,000, find a formula for the population in future years. (b) According to the formula of part (a), what will be the population in the year \(2000 ?\) (c) What is the limiting value of the population at \(t \rightarrow \infty\) ?

Find a family of oblique trajectories that intersect the family of curves \(x+\) \(y=c x^{2}\) at angle \(a\) such that \(\tan a=2\)

A man is pushing a loaded sled across a level field of ice at the constant speed of \(10 \mathrm{ft} / \mathrm{sec}\). When the man is halfway across the ice field, he stops pushing and lets the loaded sled continue on. The combined weight of the sled and its load is \(80 \mathrm{lb}\); the air resistance (in pounds) is numerically equal to \(\frac{3}{4} v\), where \(v\) is the velocity of the sled (in feet per second); and the coefficient of friction of the runners on the ice is \(0.04\). How far will the sled continue to move after the man stops pushing?

See all solutions

Recommended explanations on Math Textbooks

View all explanations

What do you think about this solution?

We value your feedback to improve our textbook solutions.

Study anywhere. Anytime. Across all devices.