Finding equation of osculating circles of ellipse

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To find the equations of the osculating circles of the ellipse 9x^2 + 4y^2 = 36 at the points (2,0) and (0,3), one must calculate the curvature at these points. The osculating circle shares the same radius as the radius of curvature and is tangent to the ellipse on the concave side. The discussion highlights confusion regarding the relevance of curvature, arc length, and parametric equations to solving the problem. A clear understanding of how to derive the curvature is essential for determining the osculating circles. Ultimately, the solution requires applying concepts from differential geometry related to curvature.
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Homework Statement


Find the equations of the osculating circles of the ellipse 9x^2 + 4y^2 =36 at the points (2,0) and (0,3)


Homework Equations





The Attempt at a Solution


I honestly have no idea what to do here. This problem is in the chapter relating to curvature and arc length, as well as unit tangent/normal/binormal vectors for vector functions, but I do not see the relation of these topics to this problem. For some reason I have the idea of parametric equations come to mind. Could someone please point me in the right direction?
 
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digipony said:

Homework Statement


Find the equations of the osculating circles of the ellipse 9x^2 + 4y^2 =36 at the points (2,0) and (0,3)


Homework Equations





The Attempt at a Solution


I honestly have no idea what to do here. This problem is in the chapter relating to curvature and arc length, as well as unit tangent/normal/binormal vectors for vector functions, but I do not see the relation of these topics to this problem. For some reason I have the idea of parametric equations come to mind. Could someone please point me in the right direction?

Do you know how to calculate the curvature at (0,3)? The osculating circle has the same radius as the radius of curvature of the ellipse and is tangent to the ellipse on the concave side.
 
Question: A clock's minute hand has length 4 and its hour hand has length 3. What is the distance between the tips at the moment when it is increasing most rapidly?(Putnam Exam Question) Answer: Making assumption that both the hands moves at constant angular velocities, the answer is ## \sqrt{7} .## But don't you think this assumption is somewhat doubtful and wrong?

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