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Double or triple integral that equals 30

  1. Oct 11, 2007 #1
    For my assignment I have to come up with a really complex double or triple integral that equals 30.
    Would you mind giving me some ideas?
  2. jcsd
  3. Oct 11, 2007 #2


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    How about picking some region in the plane (a circle perhaps) that has area 30 or a region in 3d (a sphere perhaps) that has volume 30 and set up the corresponding integral?
  4. Oct 11, 2007 #3

    Gib Z

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    Set up the integrals as a function and solve accordingly, I will start an example for a single integral.

    Choose a function, set that as the integrand, set one limit of the integral as another variable, and solve the new function to 30.

    eg I choose an integrand x^2.

    So I let [tex]f(t)=\int^t_0 x^2 dx[/tex]

    Apply the fundamental theorem of calculus we get
    [tex]f(t) = \frac{t^3}{3}[/tex]
    So now we can let f(t)=30 and solve accordingly.

    Do the same but for a double or triple integral.
  5. Oct 11, 2007 #4


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    1) Pick a function
    2) Pick a region/volume
    3) Integrate
    4) Normalize to 30
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