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Homework Help: Does dx/dy = 1/(dy/dx) ?

  1. Jul 8, 2011 #1
    I was logged out when trying to post and lost everything :cry:


    Without the background of the question cause I've lost all the equations and everything, i just needed to know if dx/dy = 1/(dy/dx)
     
  2. jcsd
  3. Jul 8, 2011 #2

    Pengwuino

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    Gold Member

    Yes for the most part. There are some basic stipulations I believe, but I'll let the mathematicians point that out.
     
  4. Jul 8, 2011 #3

    Dick

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    Sure, it's true.
     
  5. Jul 8, 2011 #4
    The problem:
    Youre given
    jF9e7.png

    Then it says:
    kXRtI.png
    Ilc6t.png
    WluMz.png


    My solution:
    O7Xhe.png
    First type:
    n5gfO.png
    Second type:
    PAVfb.png



    It seems to easy to be right.. Though it's part of a worded problem so I could be missing something
     
    Last edited: Jul 8, 2011
  6. Jul 8, 2011 #5

    Dick

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    That basically looks ok to me. Is replacing alpha with c in the second part just a typo?
     
  7. Jul 8, 2011 #6
    Yeah, well I used wolfram to input my answers so it's readable and didn't have that symbol handy. It's the symbol for proportion right?
     
  8. Jul 8, 2011 #7

    Dick

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    From what you said in defining dV/dt, it doesn't look like they mean it's 'proportional to'. They are just saying dV/dt is equal to -alpha*(h+R) where alpha is a constant. Not the 'proportional to' symbol. You could simplify (h+R)/(R^2-h^2) a bit.
     
  9. Jul 9, 2011 #8
    Thank you for clearing that up Dick.
     
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