robertjford80
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Homework Statement
I'm just interested in knowing where the 4 comes from in front of the integral.
Measuring volume of spheres using triple integrals
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I'm just interested in knowing where the 4 comes from in front of the integral.
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hi robertjford80! 
that 4∫0π/2 is really ∫02π …
i suppose the writer thought it looks confusingly like ∫00, though i see nothing wrong with it!
that 4∫0π/2 is really ∫02π …
i suppose the writer thought it looks confusingly like ∫00, though i see nothing wrong with it!
robertjford80
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Ok, pretty unexpected but I guess it makes sense.
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In other words, they are using the circular symmetry of the figures, integrating from 0 to [itex]\pi/2[/itex], rather than from 0 to [itex]2\pi[/itex], then multiplying by 4.