Evaluating Integral: \int\frac{4}{x^2-1}

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Homework Statement


[tex]\int[/tex][tex]\frac{4}{x^2-1}[/tex]



Homework Equations





The Attempt at a Solution


I thought I had this right...

[tex]\frac{4}{x^2-1}[/tex] = 2 ([tex]\frac{1}{x-1}[/tex]-[tex]\frac{1}{x+1}[/tex])

therefore,

[tex]\int[/tex][tex]\frac{4}{x^2-1}[/tex]=2(ln(x-1)-ln(x+1))

I then have to evaluate from 2 to 3 and I get .814, but it isn't right.
 
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Nevermind, I believe I figured it out.

Edit: Okay, I don't understand where I went wrong. Any help please?
 
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I get log(9/4) ≈ 0.81093
Perhaps you entered it wrong in a calculator?
 
Oh gees... rounding error... thanks