Tangent Line Equation for Ellipse: Parametric Equations at (1,2,2)

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Homework Statement


The ellipsoid 4x^2 + 2y^2 + z^2 = 16 intersects the plane y = 2 in an ellipse. Find parametric equations for the tangent line to this ellipse at the point (1,2,2)

Homework Equations


x = x0 + at
y = y0 + bt
z = z0 + ct

The Attempt at a Solution


Well i know that x0,y0 and z0 are given by the point(1,2,2) and that's pretty much it. I don't know how to use the information given in the first part of the question.
I put y=2 in the ellipsoid equation and got 4x^2 + z^2 = 8. Now what?
 
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mattibo said:

Homework Statement


The ellipsoid 4x^2 + 2y^2 + z^2 = 16 intersects the plane y = 2 in an ellipse. Find parametric equations for the tangent line to this ellipse at the point (1,2,2)


Homework Equations


x = x0 + at
y = y0 + bt
z = z0 + ct

The Attempt at a Solution


Well i know that x0,y0 and z0 are given by the point(1,2,2) and that's pretty much it. I don't know how to use the information given in the first part of the question.
I put y=2 in the ellipsoid equation and got 4x^2 + z^2 = 8. Now what?
Great! Now find a tangent line to that ellipse at x= 1, z= 2. What that will give you will probably be something line z= ax+ b. Okay, let x= t, the parameter. x= t, z= at+ b and, of course, y= 2.
 
Prove $$\int\limits_0^{\sqrt2/4}\frac{1}{\sqrt{x-x^2}}\arcsin\sqrt{\frac{(x-1)\left(x-1+x\sqrt{9-16x}\right)}{1-2x}} \, \mathrm dx = \frac{\pi^2}{8}.$$ Let $$I = \int\limits_0^{\sqrt 2 / 4}\frac{1}{\sqrt{x-x^2}}\arcsin\sqrt{\frac{(x-1)\left(x-1+x\sqrt{9-16x}\right)}{1-2x}} \, \mathrm dx. \tag{1}$$ The representation integral of ##\arcsin## is $$\arcsin u = \int\limits_{0}^{1} \frac{\mathrm dt}{\sqrt{1-t^2}}, \qquad 0 \leqslant u \leqslant 1.$$ Plugging identity above into ##(1)## with ##u...

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