Dismiss Notice
Join Physics Forums Today!
The friendliest, high quality science and math community on the planet! Everyone who loves science is here!

Homework Help: Logarithm Help

  1. Oct 22, 2011 #1
    I'm trying to teach myself logs for a statistics quiz... I know this is probably easy but i never really learned logs.

    1. The problem statement, all variables and given/known data
    I have to take the logarithm of both side of y=.70 + .59x


    2. Relevant equations
    n/a

    3. The attempt at a solution

    y=.70+.59x

    So i get Logy= Log.70 + Log (.59x)
    Logy = -.1549 + log.59x

    I dont know what to do with the log(.59x) Can i separate the .59 and the x somehow?
     
  2. jcsd
  3. Oct 22, 2011 #2

    gb7nash

    User Avatar
    Homework Helper

    No. You can't do this. We only know that log(ab) = log(a) + log(b). The correct equation is:

    Log(y) = Log(.70+.59x)

    What is it you're trying to do?
     
  4. Oct 22, 2011 #3
    I just need to take the log of both sides and simplify.

    So I get log(y) = log(.70+.59x)

    I cant seem to find any laws of logs that lets me simplify log(.70+.59x)

    Is that how the equation can be left?
     
  5. Oct 22, 2011 #4

    gb7nash

    User Avatar
    Homework Helper

    Pretty much. There's not much else you can do with that equation.
     
  6. Oct 22, 2011 #5
    ok thanks a bunch
     
  7. Oct 22, 2011 #6

    Mark44

    Staff: Mentor

    Why do you think you need to do this? What's the context from which this arises?
     
Share this great discussion with others via Reddit, Google+, Twitter, or Facebook