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File: 1762912609923.jpg (187 KB, 1179x1015)
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You know, I am somewhat of a mathematician myself.
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>>16844213
Of course that fag doesn't use dot notation for time derivatives.
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>>16844254
For me? It's the topological notation.
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>>16844265
I'd like to see the wave equation written out like that.
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File: magic runes.png (460 KB, 920x640)
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>>16844254
>>
So true, here’s a trillion dollars for that incredible insight.
>>
every time i see the limit notation it really makes me wonder how much of mathematics is just experimentation with logical reasoning even if it doesn't make sense initially.
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>>16844213
so much this
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>>16844213
It's a very good formula. One of the best formulas
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>>16844213
all of that just to grab one of the coefficients of the f(x+h) expansion.
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>>16844213
elon's such a fag lol
although at least he's more sovlful and funny than the other billiontards
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>>16844626
A lot for sure. Some giga-autist sorts the details out later, after the creative chadmatician shits out the cool new maths.
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>>16844254
newton lost
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>>16844265
There's a solution begging for a problem.
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>>16845073
Kek
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>>16844265
Source?
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>>16844213
Are fractions the closest thing mankind has to God?
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>>16848313
3000 years too late, Pythagoras-pretender
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>>16844213
What's wrong with this
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>>16848373
Elong desperately wants to be seen as a science visionary despite just wanting the $ and tries to do it by feigning plebeian fascination with a formula where even "minus" is labeled.
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>>16844314
[eqn] \left(\lim_{h \to 0} \frac{f'\left(x_1,x_2,x_3,t+h\right)-f'\left(x_1,x_2,x_3,t\right)}{h}\right)^2 =c^2 \left( \sum_{i=1}^{3} \lim_{h \to 0} \frac{f'\left(\left(x_1,x_2,x_3\right)+h\mathbf{e}_i,t\right)-f'\left(x_1,x_2,x_3,t\right)}{h} \right) [/eqn]

Here you go, the 3D wave equation written out in terms of the definition of the partial derivative.

What do you think?
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>>16849955
wait a second, f' on the left hand side refers to the first time derivative, but f' on the right hand side refers to the first spatial derivative. and the left side is squared for no reason. this is all wrong.
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>>16848383
He's just sharing a meme and adding a caption though
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>>16849955
>>16849973
[eqn] \lim_{h \to 0} \frac{f_t\left(x_1,x_2,x_3,t+h\right)-f_t\left(x_1,x_2,x_3,t\right)}{h} =c^2 \left( \sum_{i=1}^{3} \lim_{h \to 0} \frac{f_{x_i}\left(\left(x_1,x_2,x_3\right)+h\mathbf{e}_i,t\right)-f_{x_i}\left(x_1,x_2,x_3,t\right)}{h} \right) [/eqn]
You're right. I fixed it now.
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>>16844213
The guy who posted it "for those who like calculus" is even dumber. Seriously, the definition of derivative is the best you got for calculus enjoyers? How fucking dumb is twitter these days
>>
>>16850089
>>16844314
yeah this looks right but it's easier to frame this as a finite difference problem:
[eqn]
\frac{df}{fx} = lim_{\Delta x ->0} \frac{f(x+\Delta x) - f(x)}{\Delta x}
[/eqn]
now do this again but from the other side and you get the centered finite difference for the second derivative:
[eqn]
\frac{d^2f}{dx^2} = lim_{\Delta x ->0} \frac{ \frac{ f(x+\Delta x) - f(x)}{\Delta x} - \frac{ f(x) - f(x-\Delta x)}{\Delta x} }{\Delta x} \\
\frac{d^2f}{dx^2} = lim_{\Delta x ->0} \frac{f(x+\Delta x) - 2 f(x) + f(x-\Delta x)}{\Delta x^2}
[/eqn]
so the wave equation becomes:
[eqn]
\frac{\partial^2u}{\partial t^2} = c^2 \sum_{i=1}^3 \frac{\partial^2u}{\partial x_i^2} \\
lim_{\Delta t ->0} \frac{u(x_1, x_2, x_3, t+\Delta t) - 2 u(x_1, x_2, x_3, t) + u(x_1, x_2, x_3, t-\Delta t)}{\Delta t^2} = c^2 lim_{\Delta x ->0} \left( \sum_{i=1}^3 \frac{u(x_i+\Delta x, t) - 2 u(x_1, x_2, x_3, t) + u(x_i-\Delta x, t)}{\Delta x^2} \right)
[/eqn]
at this point you can rearrange and solve for [math]u(x_1, x_2, x_3, t+\Delta t)[/math], plug in some boundary and initial conditions and some small values for the infinitesimals and you have a numerical method.
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>>16850186
typo in the first equation left hand side is
[math]\frac{d f}{d x}[/math]
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>>16850086
it's a meme for people who like the idea of math but don't actually do math
by sharing it, elon is outing himself as someone who likes the idea of math, but doesn't actually do math
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>>16850186
>>16850089
Actually, it's been awhile since I saw the centered finite difference,
but the wave equation does looks great extended.
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>>16844213
You're telling me this nigga got a physics degree?
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>>16844213
E=mc2 + AI
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>>16848136
looks like a ChatGPT output but Brown's "Topology and Groupoids" uses that exact notation (i.e. [math]\mathcal{N}_X(x)[/math] to refer to the neighborhood of the point x in X)
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>>16850603
This
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>>16850603
kek
>>
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>>16844265
>>
>>16844213
Is Elon Garrison an Indian?



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