Does (LN x)^3 = LN^3 x ?

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- Mar 23rd 2008, 07:02 PMkid funky friedLn X
Does (LN x)^3 = LN^3 x ?

- Mar 23rd 2008, 07:06 PMtopsquark
It depends on the context. $\displaystyle ln^3(x)$ can either mean $\displaystyle ln(x) \cdot ln(x) \cdot ln(x)$ or it can mean $\displaystyle ln(ln(ln(x)))$, which are two

*very*different things. I typically use it as the former expression, but there are cases where you would want to use it for the latter.

Edit: By the way, note that the function is ln(x), not Ln(x) or LN(x). Mathematics (and Physics, and Engineering, and...) is a "case-sensitive" field of study.

-Dan - Mar 23rd 2008, 07:07 PMmr fantastic
- Mar 23rd 2008, 07:12 PMkid funky friedthx
thx.

I will make sure to use the proper case next time.

My answer book was using both expressions so i was beginning to wonder. - Mar 24th 2008, 03:07 AMPlato
In may be helpful to note that the notation $\displaystyle \left( {\ln \left( x \right)} \right)^n $ is used by almost all computer algebra systems.