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Homework Help: Can someone help me with this log question?

  1. Jan 21, 2009 #1
    If [tex]log_2 (5)[/tex] = x and [tex]log_2 (3)[/tex] = y , determine an expression for [tex]log_2 (15/2)[/tex], in terms of x and y.
    A. xy
    B. x + y
    C. xy - 1
    D. x + y - 1

    I'm suppose to solve this by hand but it doesn't seem possible. I tried so many ways but the does not come out as D. which is the answer Can someone explain the steps to this problem? Thanks!
  2. jcsd
  3. Jan 22, 2009 #2


    Staff: Mentor

    Hint: log2(15/2) = log2(15) - log2(2)
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