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Simple Algebra Question

  1. Feb 25, 2013 #1
    1. The problem statement, all variables and given/known data
    how are these two problems equivalent?

    2. Relevant equations
    9 * ln | sqrt(4+x^2)/2 + x/2 | --->> = 9 * ln | sqrt(4+x^2) + x|

    3. The attempt at a solution
    i assume this has something to do with log rules.
  2. jcsd
  3. Feb 25, 2013 #2


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    Science Advisor
    Homework Helper

    Those aren't problems, they are expressions. And they aren't equivalent, they are different numbers when you put a value in for x. What is true is that they have the same derivative. ln(f(x)/2)=ln(f(x))-ln(2). If you differentiate the derivative of ln(2) is zero.
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