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Homework Help: Surface Integral

  1. Oct 31, 2005 #1
    Hi! I don't know how to approach this problem. I need a little bit of help please. Here is the problem:
    Find the surface area of that portion of the sphere [tex]x^2 +y^2 + z^2 =a^2 [/tex] that is above the xy-plane and within the cylinder [tex] x^2 + y^2 = b^2, 0 \leq b \leq a[/tex]
     
  2. jcsd
  3. Oct 31, 2005 #2
    Give us some input on the integral youre thinking about..
     
  4. Oct 31, 2005 #3

    saltydog

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    Two things Mathwurkz:

    1. That's not a surface integral but rather a calculation to determine the surface area. Surface integrals are different. Check them out if you wish.

    2. Draw a picture: Ideally, draw one in 3-D using Mathematica or other software. But even a cross section would be helpful. Once you have an accurate picture in mind, it's easier to construct the integral for the surface area.

    Edit: One more thing Mathwurkz:

    What happens when a=b? Then the problem is easy right? Anyway, that's a good way to check your integration: If it works for this simple case which is known by inspection, then that gives some confidence it's correct when b is less than a.
     
    Last edited: Oct 31, 2005
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