Use the properties of logarithma to xpand the logarithmic function

AI Thread Summary
To expand the logarithmic function ln[(x^2+1)(x-1)], the initial correct step is to separate it into ln(x^2+1) + ln(x-1). However, the subsequent attempt to further break down ln(x^2+1) into ln(x^2) + ln(1) is incorrect, as ln(1) equals zero and does not contribute to the expansion. The discussion highlights that x^2 + 1 cannot be factored over the reals, which complicates further simplification without involving imaginary numbers. Ultimately, the focus remains on correctly applying logarithmic properties without missteps in factoring. Understanding these properties is crucial for accurately expanding logarithmic functions.
Ki-nana18
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Homework Statement


Use the properties of logarithma to xpand the logarithmic function ln[(x2+1)(x-1)]


Homework Equations





The Attempt at a Solution


[ln x2+ln 1]+[ln x-ln 1]
2 ln x+ln x
 
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the first step makes sense: ln[(x^2+1)(x-1)]=ln(x^2+1)+ln(x-1)

but then you continued: ln(x^2+1)=ln(x^2)+ln(1)

You can't do that, but you can do something else to the x^2+1...
 
gamer_x_ said:
the first step makes sense: ln[(x^2+1)(x-1)]=ln(x^2+1)+ln(x-1)

but then you continued: ln(x^2+1)=ln(x^2)+ln(1)

You can't do that, but you can do something else to the x^2+1...
Is the something else you're thinking about factoring x^2 + 1?
 
I just realized I was stupidly thinking of x^2-1 not x^2+1. You can't really factor that term unless you go into imaginary numbers.
 
That's what I thought you might be thinking.
 
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