Here is the statement: ln(ln e) = 0?
Matthew Martinez
I'm not quite sure why this is true, perhaps a better explanation will help me out. I understand that a natural log has to be a positive number.
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$\begingroup$$e = e^1$
$1 = e^0$
So $\ln(e) =1$ and $\ln(1) = 0$.
And $\ln(\ln e) = \ln (1) = 0$.
$\endgroup$ $\begingroup$$\ln e = 1$.
You just have to evaluate $\ln 1$.
The input of a natural log has to be positive, the output need not be positive.
$\endgroup$ $\begingroup$$\ln x:= n$ such that $e^n=x$. So, $\ln e=n$ such that $e^n=e.$ So, $\ln e=1$. Now, $\ln 1=n$ such that $e^n=1$, which implies that $\ln 1=0$.
$$ \ln(\ln e)=\ln(1)=0.$$
$\endgroup$ $\begingroup$The natural log of a number is whatever you have to raise $e$ to, in order to get that number. So for example $\ln(10)$ is saying, "what do I need to raise $e$ to, in order to get 10?. So you could plug that in your calculator, and see $\ln(10) \approx 2.3025$ and then you could check it by seeing what $e^{2.3025}$ is.
In your case, $\ln(e)$ is saying, "what do I need to raise $e$ to, in order to get $e$? well obviously that's just 1 since $e^1 = e$. So then we are left with $\ln(1)$. "What do I need to raise $e$ to in order to get 1?". Well raising anything to the 0 power gives you 1. So the answer of what you need to raise $e$ to is, zero.
Thus $\ln(\ln(e)) = 0$
$\endgroup$ $\begingroup$$$\ln(\ln e)=\ln 1= 0$$ The logarithm on base $a$ of $a$ is always $1$, since $a^{1} = a$. In addition, it has to be $a> 0$ and $a$ other than $1$, so that there are no problems.
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