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Log help (Homework)

  1. Oct 9, 2005 #1
    I've been looking through my text book for a question even remotly similiar and no luck, if you could get me started witht this question I'd love to do it and then I'll write what I got and write it here.

    If y=x^2(a+z) determine an expression equal to log x. (Hint: you will need to take the log both sides at some point)
  2. jcsd
  3. Oct 9, 2005 #2


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    Would this property help you?

    [tex]\log a^b = b\log a[/tex]
  4. Oct 9, 2005 #3
    uhh not really, you could elaborate on that idea though?

    Would it be like...

    logx = xlog

    then xlog^2(a+z)

    Sorry I'm really confused/
  5. Oct 9, 2005 #4


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    If you take the log of both sides, you end up with:

    [tex] \log y = \log x^2^(^a^+^z^)[/tex]

    See the similarity between the b in my earlier equation and 2(a+z)? >_>
  6. Oct 9, 2005 #5
    okay... I kind of get it...

    I did this...

    log(y/x) = 2a + 2z

    so thats logx = (2(a+z))/y

    I'm still stuck
  7. Oct 9, 2005 #6


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    The question asks, determine an expression for log x? I'm confused about what you are trying to accomplish. Following from:

    [tex] \log y = \log x^2^(^a^+^z^)[/tex]
    [tex] \log x = \frac{\log y}{2(a+z)}[/tex]
  8. Oct 9, 2005 #7


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    Pepsi, please post all coursework related questions in the Homework Help section.

    Also, you need to relearn the properties of logarithms first. Please go over this chapter in your text again. For instance, log(y)/log(x) is not the same as log(y/x).
    Last edited: Oct 10, 2005
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