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This might be a simple question, but where would I write the power if I had a logarithmic function?

Instinctively I would write it as $\log^y(x)$. But I'm not sure if this is correct. Should I be writing $(\log(x))^y$ instead?

Thanks for the help!

MathMajor
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Qub1
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    Those two are the same, but just be careful to note that $(\log_{b}(a))^c\neq\log_{b}(a^c)$ –  May 08 '15 at 19:57
  • Okay thanks, so these two notations should both be acceptable on say an official exam? – Qub1 May 08 '15 at 19:58
  • Yes it should be understood. See this if you want to read more: http://math.stackexchange.com/questions/150546/what-does-log2x-mean –  May 08 '15 at 20:03
  • What's acceptable on an "official" exam is up to the official who gets to mark the exam, and that's the person you should ask. – Gerry Myerson May 08 '15 at 23:17

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Write $(\log x)^y$; you don't need more parentheses than that. There are problems with writing $\log^n\!x$. By analogy with (say) $\cos^n\!x$, it might be interpreted as $(\log x)^n$. However, it might also be taken to mean (quite logically) $\log...\log x$ (where there are $n$ applications of the logarithmic function).

John Bentin
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