Finding Cartesian equation of parametric surface.

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To find the Cartesian equation of the parametric surface defined by the equations x=2cos(t)cos(s), y=3sin(s), and z=sin(t)cos(s), the discussion suggests squaring each term and exploring the relationship between them. The user is unsure how to proceed after obtaining the squared terms and is considering whether constants α and β can be determined to express the equation in the form x² + αy² + βz² = constant. Additionally, the problem involves finding the equation of the tangent plane at the specific parameters S = 0 and t = π/2. The conversation highlights the need for clarity on the next steps in deriving the Cartesian equation and the tangent plane. Overall, the discussion revolves around transforming parametric equations into a Cartesian form and calculating the tangent plane.
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Homework Statement


Find the Cartesian equation of the parametric surface: [2cos(t)cos(s), 3sin(s), sin(t)cos(s)]

Find eqn. of the tangent plane when S = 0, t = pi/2

Homework Equations


The Attempt at a Solution



I'm not quite sure what to do. All I've done is squared each term, which gave me.

4cos^2(t)cos^2(s)
9sin^2(s)
sin^2(t)cos^2(t)
 
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x=2\cos t\cos s

y=3\sin s

z=\sin t \cos s

Can't you find \alpha and \beta so that x^2+\alpha y^2 + \beta z^2= constant?
 
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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