Maximizing Area of an Ellipse Passing Through a Fixed Point

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Discussion Overview

The discussion revolves around finding the equation of an ellipse that is symmetric with respect to the coordinate axes and passes through a fixed point (h, k), with a focus on maximizing or minimizing the area of the ellipse. The conversation includes mathematical reasoning and exploration of different approaches to the problem.

Discussion Character

  • Mathematical reasoning
  • Exploratory
  • Homework-related

Main Points Raised

  • One participant presents an equation for the ellipse and attempts to derive the conditions for maximizing the area, expressing uncertainty about their approach.
  • Another participant clarifies that the problem may actually involve minimizing the area, noting that the maximum area is unbounded, and discusses the use of Lagrange multipliers to solve the problem.
  • A later reply suggests that the problem should be approached using one variable or parametric equations, given the audience's background in mathematics.
  • There is a suggestion to solve the constraint for one variable and use substitution to create an objective function in one variable.

Areas of Agreement / Disagreement

Participants express differing views on whether the problem is about maximizing or minimizing the area of the ellipse. There is no consensus on the correct approach or solution method, and the discussion remains unresolved.

Contextual Notes

Some participants note the limitations of the audience's mathematical background, indicating that solutions should be accessible without advanced techniques involving multiple variables.

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347) An ellipse slmetric with respect to the coordinate axes handle: through the fixed point (h, k). Find The equation of the ellipse's?
area maximum
answer k2/SUP] h 2 + h 2 y 2 = 2 h 2 k2 The equations here must be
y = m(x-h)+k

Parametrizing
x= a cos(t)
y = b(sen(t)

D= (a cost-h)2+((macosth-h)2+ k -k)2

am I right?
Becuse I could not get the right answer
 
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leprofece said:
347) An ellipse slmetric with respect to the coordinate axes handle: through the fixed point (h, k). Find The equation of the ellipse's?
area maximum
answer k2/SUP] h 2 + h 2 y 2 = 2 h 2 k2 The equations here must be
y = m(x-h)+k

Parametrizing
x= a cos(t)
y = b(sen(t)

D= (a cost-h)2+((macosth-h)2+ k -k)2

am I right?
Becuse I could not get the right answer

If I understand it correctly, the problem is to find an ellipse symmetric about the coordinate axes and passing through the fixed point $(h,k)$, such that the ellipse has the minimum possible area. (The question says maximum area, but in fact the only critical point is a minimum, and the maximum area is unbounded.)

The equation of the ellipse is $\dfrac{x^2}{a^2} + \dfrac{y^2}{b^2} = 1$, and we have to choose $a$ and $b$ so as to minimise the area of the ellipse, which is $\pi ab.$ The condition for the point $(h,k)$ to lie on the ellipse is $\dfrac{h^2}{a^2} + \dfrac{k^2}{b^2} = 1$, or $a^2k^2 + b^2h^2 = a^2b^2$. So we want to minimise $ab$ subject to the constraint $a^2k^2 + b^2h^2 = a^2b^2$. The usual way to solve problems of that sort is to use the method of Lagranga multipliers.
 
Opalg said:
If I understand it correctly, the problem is to find an ellipse symmetric about the coordinate axes and passing through the fixed point $(h,k)$, such that the ellipse has the minimum possible area. (The question says maximum area, but in fact the only critical point is a minimum, and the maximum area is unbounded.)

The equation of the ellipse is $\dfrac{x^2}{a^2} + \dfrac{y^2}{b^2} = 1$, and we have to choose $a$ and $b$ so as to minimise the area of the ellipse, which is $\pi ab.$ The condition for the point $(h,k)$ to lie on the ellipse is $\dfrac{h^2}{a^2} + \dfrac{k^2}{b^2} = 1$, or $a^2k^2 + b^2h^2 = a^2b^2$. So we want to minimise $ab$ subject to the constraint $a^2k^2 + b^2h^2 = a^2b^2$. The usual way to solve problems of that sort is to use the method of Lagranga multipliers.

thanks sorry but the students here haven't studied 2wo variables yet so it should be answerred or with one variable or with parametrics So I wrote parametrics in what I did
can you or anyone help me ??
 
Perhaps you could solve the constraint for either of the two variables and then use substitution to obtain an objective function in one variable...(Thinking)
 

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