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Solving double integrals

  • #1

Homework Statement



f(x,y,z) = g(√(x^2 + y^2 + z^2))
g(t) = t-5
evaluate ∯ f(x,y,z)ds

where S is sphere x^2 + y^2 + z^2 = 9


Homework Equations





The Attempt at a Solution



i don't know how to go about it. can someone help me with this, how to approach this from start to end. i will solve it, but i need to know the steps in doing it.
 

Answers and Replies

  • #2
tiny-tim
Science Advisor
Homework Helper
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hi myfunkymaths! :smile:

(have a square-root: √ and try using the X2 icon just above the Reply box :wink:)
f(x,y,z) = g(√(x^2 + y^2 + z^2))
g(t) = t-5
evaluate ∯ f(x,y,z)ds

where S is sphere x^2 + y^2 + z^2 = 9
uhh? isn't that just integrating r - 5 over the sphere r = 3 ? :confused:
 
  • #3
hi myfunkymaths! :smile:

(have a square-root: √ and try using the X2 icon just above the Reply box :wink:)


uhh? isn't that just integrating r - 5 over the sphere r = 3 ? :confused:
so what function do i integrate twice? and with what bounds was it
 
  • #4
tiny-tim
Science Advisor
Homework Helper
25,832
250
but it's constant!!
 

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