Talk:Intermediate Algebra/Logarithms

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I believe that we should add at this page the definition a^x=z <=> x= log_a(z) The ln (logarith with base e) should also be covered.

Oh, we need even more stuff than this. For one thing, logarithms aren't simply rearrangements of other equations - they are a problem-solving method involving that, but they have their own properties which need to be proven. One does not fully understand a logarithm without proofs.
For that matter, there is a property missing from the page: log_a(b) / log_a(c) = log_c(b). It's called "change of base". Have a look at the full article on Wikipedia: Logarithm --Deriamis 22:24, 25 July 2006 (UTC)
I added the change of base rule, there's also a couple other properties of logs (like a special case of the change of base rule, log_b(a) = 1/log_a(b)) that may or may not be important enough to put in there. I'm not sure, do you think I should keep the example in there? Mattb112885 02:20, 29 July 2006 (UTC)