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  1. #1
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    help

    plz solve it
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  2. #2
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    Krizalid's Avatar
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    First two questions are not well typed. It should be $\displaystyle dy\,dx.$

    Now, to make polar transform, draw the region you're integrating.

    The first integral in polar coordinates is $\displaystyle \int_0^{2\pi } {\int_0^1 {r\,dr\,d\theta } } .$ (I dunno if this is the integral, but its result agrees with the double integral in cartesian coordinates.)
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  3. #3
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    Krizalid's Avatar
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    The second question is equal to the first one.

    We have a full circle. This in polar coordinates

    $\displaystyle \int_0^{2\pi } {\int_0^a {r\,dr\,d\theta } } .$

    Or by reversing integration order. (Fubini-type Theorem.)
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  4. #4
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    Thanks

    Thank You Krizalid.
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