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Double integral

  1. Aug 4, 2009 #1
    For the double integral [tex]\int\int_R[/tex] sqrt(x^2+y^2) dx dy where R is the unit circle.
    I got[tex]\int_0^\pi\int_1^1[/tex] sqrt(r2) r dr dtheta
    Then after the integration I got an answer of 2[tex]pi[/tex]/3 as my final answer.
    Is this right.
    The bottom of the 2nd integral is -1 not 1
  2. jcsd
  3. Aug 4, 2009 #2


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    Hi squenshl! :smile:

    (have a pi: π and a theta: θ and try using the X2 tag just above the Reply box :wink:)

    (and you needed \int_{-1}^1)

    erm :redface:you can't have r less than 0!! :wink:
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