Surface Integral between planes

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SUMMARY

The discussion focuses on calculating the surface integral ∫∫s x √(y² + 4) over the surface defined by the equation y² + 4z = 16, constrained by the planes x=0, x=1, and z=0. The surface area integral formula is utilized, transforming the double integral into ∫∫f(x,y,g(x,y)) √((∂z/∂x)² + (∂z/∂y)² + 1) dA. The calculated surface area A(S) is √(1+(1/4)y²), which simplifies to 1/2 √(4+y²). The integration limits are determined by the intersection of the surface with the x-y plane, resulting in a square footprint of 1x4.

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Homework Statement



∫∫s x √(y2 + 4) where S: y2 + 4z = 16, and portion cut by planes x=0, x=1, z=0.

Homework Equations



I attempted to solve using the surface area integral formula, whereby this double integral is transformed to ∫∫f(x,y,g(x,y)) √((∂z/∂x)2 + (∂z/∂y)2 + 1) dA

The Attempt at a Solution



Solving for z in the S region, and finding partials with respect to x and y yields A(S) of √(1+(1/4)y2) which can be rewritten as 1/2 √(4+y2)

Multiplying this by the original function, which is a function of just x and y, gives ∫∫ x/2*(4 + y2) dA.

I'm having trouble finding the limits of integration for the given planes.
 

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The limits of integration are over the foot-print in the x-y plane of the surface you're integrating over right? You drew it? It's that paraboloid-cylinder cut at the planes of x=0 and x=1 above the x-y plane and you can figure where it cuts through the x-y plane by the equation z=4-1/4 y^2. It's just a square 1x4.
 

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