Is ln(√e^π)/π a rational number?

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johann1301
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is ln(√eπ)/π a rational number?

where π =3.14...
 
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Isn't it a half?
 
but my textbook says its an irrational number, how can that be?
 
$$
\begin{align}

\frac{ \ln{ \sqrt{ e^\pi } } }{\pi} &= \frac{ \ln{ e^\frac{\pi}{2} } }{\pi}\\

&= \frac{1}{\pi} \frac{\pi}{2}\\

&= \frac{1}{2}

\end{align}
$$
The ## \sqrt{e^\pi} ## is equivalent to ##e^{\frac{\pi}{2}}##, so the natural log cancels with ##e## and you're left with ##\frac{(\frac{\pi}{2})}{\pi}## which is ##\frac{1}{2}##.
 
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