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Homework Help: Logarithm help

  1. Apr 17, 2006 #1
    ok im having abit of trouble solving the find x type of questions
    the 3 questions ive got are

    1.) solve x for the following equation
    loge(x) + loge(3x+1) = 1

    2.) solve x
    2loge(x) + loge4 = loge(9x-2)

    3.) Given that loga(N) = 1/2(loga(24) - loga(0.375) - 6loga(3) ) find the value of N ..now i was wondering if ne-one would be able to help me with these types of questions cause i dont know how to approach em:bugeye:
     
  2. jcsd
  3. Apr 17, 2006 #2

    dav2008

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    Are you familiar with logarithmic identities?

    [tex]log(a)+log(b)=log(ab)[/tex]
    [tex]log(a)-log(b)=log(\frac{a}{b})[/tex]
    [tex]b\cdot log(a)=log(a^b)[/tex]
     
  4. Apr 17, 2006 #3

    Integral

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    You must have been studying the properties of logs.

    What is logx + logy equivenent to?

    What about alogx ? Look at your basic properties and think about how to apply them to your problem.
     
  5. Apr 17, 2006 #4
    Yeah i am familiar with them and when i tried applying them i got answers that didnt match when i tried putting them in a ti-83 calculator to match u can use second table to get rough answers but i would appreciate being bale to do them without a calculator
     
  6. Apr 17, 2006 #5

    Integral

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    Show us your work.
     
  7. Apr 18, 2006 #6
    oh its alright ive managed to figure out 2 and 3 after extensive rubbing out and many attempts lol now im sure if i can do them that i should be able to do the first one
     
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