Surface Integral Help: Area of Sphere Inside Paraboloid (No Quotation Marks)

Johnny Blade
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Homework Statement


What is the area of the portion of the sphere x^{2}+y^{2}+(z-a)^{2}=a^{2} that is inside the paraboloid z=x^{2}+y^{2}


Homework Equations


\int\int_{S} dS


The Attempt at a Solution



I used this

\int\int_{S} dS=\int\int_{R}\sqrt{f^{2}_{x}+f^{2}_{y}+1}dx dy

And got

=\int\int_{R}\frac{a}{\sqrt{a^{2}-x^{2}-y^{2}}}dx dy

I know that R is the projection of the surface on the xy plane, but I tried a few different ways to compute the boundaries but it never made sense. Maybe I'm just approaching it the wrong way. Anyone can help me with this?
 
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Can you please show us what you tried? Did you try solving for the bounds algebraically? Draw a diagram to aid you, and solve the equations simultaneously.
 
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