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Homework Help: Integrating from 0 to 200 of 1/(14-(.0003x^2))

  1. Jan 29, 2009 #1
    I cant figure out how to this integral. I keep coming up with the wrong answer. Can someone please show me a detailed solution?
     
  2. jcsd
  3. Jan 29, 2009 #2

    tiny-tim

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    Welcome to PF!

    Hi musichael! Welcome to PF! :wink:

    Show us what you've tried, and where you're stuck, and then we'll know how to help. :smile:
     
  4. Jan 29, 2009 #3
    ok first i did ln(14-.0003x^2) divided by the derivative of the inside. but when i plug in the definate integral values i cant get the correct answer.
     
  5. Jan 29, 2009 #4
    the answer should be 25.1
     
  6. Jan 29, 2009 #5
    I cant figure it out.
     
  7. Jan 29, 2009 #6

    tiny-tim

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    uhh? :confused:

    d/dx(ln(14-.0003x^2)) = (.006 x)/ln(14-.0003x^2).

    Try either a trigonometric substitution, or partial fractions. :wink:
     
  8. Jan 29, 2009 #7
    the function that i need to integrate is 1/(14-.0003X^2) Im pretty sure you use the Ln(14-.0003X^2)/(2(.0003x) but It doesnt work with 0 to 200
     
  9. Jan 29, 2009 #8
    I tried using partial fractions but I cant figure out how to factor the bottom expression
     
  10. Jan 30, 2009 #9

    tiny-tim

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    but the bottom is a - bx2 :frown:
     
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