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Math Help - Simple Double Integral Question

  1. #1
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    Simple Double Integral Question

    I need to evaluate this integral

    \iint\limits_{D} {\frac{1}{\sqrt {x^{2}+y^{2}} }}dA

    over the area bounded by the top half of (x-1) + y =1.

    My calculation keeps yielding 2, but this does not make logical sense because the area is a half circle of radius 1. Shouldn't the value of the integral be Pi/2 ?

    Anybody else get 2 from the integral?
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  2. #2
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    why do you think \int_D \frac{1}{\sqrt{x^2+y^2}}dA is the area? Actually \int_D dA is the area, but your integral is not.
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