Surface Area on x^2+y^2+z^2=4x, inside x=y^2+z^2

Daniel_Feldman

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Sep 30, 2005
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I need to find the area of the surface that lies on the sphere x^2+y^2+z^2=4x and inside the paraboloid x=y^2+z^2.

So I found the partial derivatives and then put them in the integrand in terms of polar coordinates. My outer limits will be 0 to 2pi, but I do not know what my inner limits will be. Is this easier to do in, say spherical coordinates?
 
Spherical coordinates will simplify things. Restating the problem as the surface of the sphere x^2 + y^2 + z^2 = 4 inside the parabaloid z + 2 = x^2 + y^2 (by translating along the x-axis 2 units and switching x and z axes), gives straightforward limits for theta: 0 to 2pi and phi: -pi/3 to pi/3, and a familiar integrand.
 
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