Well, Indistinguishable explains it better than I. But the gist is, Taylor series expansions aren’t a very interesting or informative way to describe such rich functions as the exponential and trig functions, and it’s far more elegant to describe them in terms of their more interesting properties.
Though certainly the Taylor series are the most common way to prove it, and the one you’re likely to see in textbooks.
Yes, me too, as I said on this re-animation…But I remembered “expansion,” which even graphically is clear; another proof that somethings that get in SDGQ stick around in my brain somewhere…
But a quick check showed up -0.99999… evidence. Tiz a puzzle.
It looks like it might mean something, but what it’s hard to say without more context. All the 'z’s suggest complex analysis, but that doesn’t narrow things down all that much, and besides there’s no reason one can’t use z for just any old ordinary variable.
It’s coherent enough (compare Abel’s theorem) with the conclusion at the top, but the key question is, what is it for? Clearly it was taken out of a specific context, but what was that context?
I’m just a guy who dropped out of high school and am now back in trade school. I’ve always wondered about blackboards full of scientific notation and figured I’d never have a clue.
Very quickly I found that there’s a reason trades are in demand and it’s not a joke to go back to school.
There’s a reason why you’ll never see a movie called “Larry the air conditioning guy”.
On my first day of class I was head first into the deep end and found myself face to face with said equations.
In my second semester i was nominated and inducted into the National Technical Honor Society.
after all that I may never have to do the maths out in the field due to apps and smart tools.
Some variant of the three-body problem? The trouble with blackboards like this, and the previous one, is that it is like taking a snapshot of someone’s random scratch paper, or the middle of a long proof in the middle of a lecture.
The 1/(2pi*i) is probably a hint that we’re doing a Fourier transform of something, and the Phi might be a quantum mechanical wavefunction. But the really juicy bits look like they’d be behind the guy’s head in that shot.