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Re:About the irrationality of e=2.718... (1840) by siegelzero on Tuesday January 24, 2017 @12:57PM (#13473736)
This a very terse proof. It is stated "The same method can also be used to prove that e cannot be a root of a second degree equation with rational coefficients", but if I recall correctly, the generalization for the irrationality of $e^2$ isn't entirely straightforward, mainly due to the presence of powers of 2 in the terms of the expansion.
Re:About the irrationality of e=2.718... (1840) by arglebarnacle on Tuesday January 24, 2017 @01:25PM (#13474024)
Off topic, but can you tell me whether you're using a browser extension to render $e^2$ (and if so which one!), or if you're simply using the $ character as a delimiter for humans who read and write a lot of LaTeX code?
Re:About the irrationality of e=2.718... (1840) by ajross on Tuesday January 24, 2017 @01:33PM (#13474108)
Math people can read TeX without compilation.
Re:About the irrationality of e=2.718... (1840) by siegelzero on Tuesday January 24, 2017 @01:28PM (#13474058)
It's simply a habit from LaTeX :-)
Re:About the irrationality of e=2.718... (1840) by simplicio on Tuesday January 24, 2017 @05:01PM (#13476044)
I always found it weird that despite being developed at CERN and most widely used in the early years by universities and research labs, HTML never developed a decent standard for transmitting/rendering math equations (I know that there's a math tag now, but it doesn't seem to get much use). Especially given that Latex would seem to provide a pretty widely known de-facto standard for the syntax.
Re:About the irrationality of e=2.718... (1840) by nikdaheratik on Tuesday January 24, 2017 @05:49PM (#13476515)
1) HTML is derived directly from SGML which was used to handle similar markup issues in printed texts. One of the reasons why HTML was successful was because there were already similar tools in place from SGML that could be quickly applied to handle processing and correctness. Adding math would require building a number of additional tools.

2) TeX by itself doesn't resolve very well into the DOM tree which is what parsers use to organize the markup data internally. You need a markup language that is similar to HTML if you want to make it easy for browsers, parsers, and libraries to adopt the new standard.

Re:About the irrationality of e=2.718... (1840) by mixedmath on Wednesday January 25, 2017 @01:28AM (#13479185)
This may be a little ridiculous, but I have a bookmarklet that I click on sometimes to render most LaTeX in the current window.

I use this because I'm a mathematician and I chat with some other mathematicians through Slack frequently, and this doesn't have good LaTeX support. But by clicking this, it loads MathJax from the MathJax CDN to render. We also use this on the chatrooms associated to Math.StackExchange and MathOverflow, which is why it's called ChatJax.

If this is something that interests you, you can find it on this semi-hidden page on my website: http://davidlowryduda.com/static/chatjax.html

Re:About the irrationality of e=2.718... (1840) by stablemap on Tuesday January 24, 2017 @03:01PM (#13474923)
I don't have any recommendations, but they do exist:

http://mathoverflow.net/questions/22141/how-do-i-see-latex-m...

Re:About the irrationality of e=2.718... (1840) by conistonwater on Tuesday January 24, 2017 @01:20PM (#13473978)
As pointed out in the annotation, isn't the case $e^2$ just exactly the same proof but for the special case $c=0$? And in any case, if $e^2$ were rational, then $e$ could only be rational or a quadratic irrationality.
Re:About the irrationality of e=2.718... (1840) by siegelzero on Tuesday January 24, 2017 @02:46PM (#13474789)
Yeah, this proof seems to work. I was thinking of the case where you attack $e^2$ directly, instead of going after both $e$ and $e^{-1}$.
Re:About the irrationality of e=2.718... (1840) by pmalynin on Tuesday January 24, 2017 @03:12PM (#13475015)
It can be shown by clever application of Taylor Expansion that e^2 is irrational.
Re:About the irrationality of e=2.718... (1840) by stablemap on Tuesday January 24, 2017 @02:47PM (#13474798)
Maybe it's better to write his equation as ae² - ce + b = 0. The proof would say that e isn't degree ≤ 2 over the rationals.