Solving a Tricky Natural Log Question

AI Thread Summary
The expression ln(1/x) can be simplified to -ln(x) because ln(1) equals 0. The initial confusion arose from incorrectly applying the logarithmic rule, leading to a misunderstanding of the calculator's output. Users are reminded to check their input for errors, as calculators can sometimes yield unexpected results. The power rule can also be applied, confirming that ln(1/x) equals -ln(x). Understanding these properties of logarithms is essential for accurate calculations.
Weather Freak
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I have a tricky natural log in front of me.

It's ln(1/x).

The reason it's tricky is because I thought that I could re-write it as ln(1)-ln(x), as per the rules of logs, but that doesn't seem to agree with my calculator. Is there a reason why?

Thanks!
 
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you put it in your calculator wrong?
 
Works just fine for me. Check your parenthesis or something
 
Weather Freak said:
I have a tricky natural log in front of me.
It's ln(1/x).
The reason it's tricky is because I thought that I could re-write it as ln(1)-ln(x), as per the rules of logs, but that doesn't seem to agree with my calculator. Is there a reason why?
Thanks!

And of course, log(1)= 0 so this is -ln(x). You could also have used the "power rule" to say ln(1/x)= ln(x-1)= -ln(x).

Is that what your calculator is giving you? Remember- you are supposed to be smarter than your calculator!:smile:
 
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