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Homework Help: Another log problem

  1. Oct 23, 2004 #1
    Can anyone help me with this natural log?

    ln x + ln(x+1) = 7

    I've tried putting it in quadratic form but all I get is x^2 + x - 7=0
    which doesn't seem to factor. What am I doing wrong?
     
  2. jcsd
  3. Oct 23, 2004 #2
    For one thing, your equation is wrong. It should be x^2 + x - e^7 = 0

    Second, there are methods other than factoring for solving quadratic equations.
     
  4. Oct 23, 2004 #3
    I've never seen this

    well, thanks but, I've never actually seen this type of equation. What do I do with the -e^7, or what I mean is how do I factor that? Actually, should I just use the quadratic formula?
     
  5. Oct 23, 2004 #4
    Your calculator should be able to give you a value for e^7. I am assuming that you know what e is. Then, using the quadratic formula should give you the correct answer.
     
  6. Oct 23, 2004 #5
    thanks!

    I see what you mean now, so I'll go crunch the numbers! Thanks a lot :)
     
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