Is ln(√e^π)/π a rational number?

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Discussion Overview

The discussion revolves around whether the expression ln(√e^π)/π is a rational number. Participants explore the mathematical properties and implications of this expression, including its evaluation and the nature of its result.

Discussion Character

  • Mathematical reasoning, Debate/contested

Main Points Raised

  • One participant questions if ln(√e^π)/π is a rational number.
  • Another participant suggests that the complexity of eπ could warrant extensive discussion.
  • One participant proposes that the expression simplifies to a value of 1/2.
  • A later reply acknowledges the previous suggestion but expresses uncertainty about the correctness of that simplification.
  • Another participant cites their textbook claiming the expression is irrational, questioning the validity of that assertion.
  • A subsequent post reiterates the textbook's claim of irrationality and suggests it could be incorrect.
  • A mathematical derivation is presented, showing the simplification of ln(√e^π)/π to 1/2, indicating it is rational.

Areas of Agreement / Disagreement

Participants express differing views on the nature of the expression, with some suggesting it is rational and others claiming it is irrational. The discussion remains unresolved regarding the correctness of these claims.

Contextual Notes

There are references to differing interpretations of the expression's nature based on textbook information, and the mathematical steps presented may depend on specific definitions or assumptions about irrationality.

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

where π =3.14...
 
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Wow, e alone not hard-enough? You could write a whole paper, if not a small book in answering this.
 
Isn't it a half?
 
You may be right; I guess I jumped the gun.
 
but my textbook says its an irrational number, how can that be?
 
johann1301 said:
but my textbook says its an irrational number, how can that be?

Your textbook could be wrong!
 
$$
\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}##.
 
Last edited:

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