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Rearranging equation

  1. Aug 5, 2005 #1
    I'm trying to rearange an equation but don't manage to get the right results so I guess the rearranging did not work out properly. Where is my mistake?

    Z=Y+(X/W)Ve(^(WU) -1)

    my sollution:
    U=ln (Z/((X/W)U))+1 /W

    thanks a lot

  2. jcsd
  3. Aug 5, 2005 #2


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    I don't really get this equation. Can you write it in a clearer way? What's V, and is it e ^(WU - 1) or e ^(WU) - 1?
    Viet Dao,
  4. Aug 5, 2005 #3


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    What happens to V? Why is there a U on the right? Is that supposed to be V? And yeah, what does e(^(WU)-1) mean? Did you mean to write e^(WU-1)?
  5. Aug 5, 2005 #4


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    Im not clear on what e(^(WU)-1) could mean. I'm going to assume that it was e^(WU-1) (eWU-1). The other possiblility is e^(WU)- 1 (eWU-1.

    If Y= 0, then the equation is really Z= (X/W)V eWU-1. Divide both sides by (X/W)V and we have (WZ)/(XV)= eWU-1. Take the natural logarithm of both sides to get ln((WZ)/(XV))= WU-1. Add 1 to both sides: WU= 1+ ln((WZ)/(XV). Finally, divide both sides by W and you have
    U= (1+ ln((WZ)/(XV)))/W.

    Of the problem was, in fact, Z= (X/W)V (eWU-1) then start out the same as above- divide by (X/W)V to get (WZ)/(XV)= eWU-1.
    Add 1 to both sides: eWU= 1+(WZ)/(XV). Take logarithms of both sides: WU= ln(1+ (WZ)/(XV)). Finally, divide both sides by W:
    U= ln(1+(WZ)/(XV))/W.
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