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Physicist behavior
Thank you for the belly laugh!
Hum… I don’t think the integral “operator” applies by multiplication.
You can put the dx at the beginning of the integral, but not before it.
Physicists be like: whitness me
Nobody on your link is treating the integral “operator” as multiplicative.
dx \int f(x)is blatantly different from\int f(x) dx
If you were using nonstandard analysis with dx an infinitesimal you could put it outside I guess. Maybe with differential forms too?
Switch it with a summation operator and see if it makes sense. The problem isn’t the operation by itself, but the fact that the operator implies an argument application, like a function.
In the case of dx as an infinitesimal it makes sense. You are making a sum of all the values of the function in the integral range and multiplying with a constant dx.
In the context of differential forms, an integral expression isn’t complete without an integral symbol and a differential form to be integrated.
My initial thought was that it’s surprising that the engineer is using i whereas the mathematician is using j. But I know some engineers who are hardcore in favour of i. No mathematicians who prefer j though. So if such an engineer were dating a mathematician of all people who used j, I could see that being ♠ .
As a physicist I can’t understand why would anyone complain about a +jb or $\int dx f(x)$. Probably because we don’t fuck
I think rather
d/dxis the operator. You apply it to an expression to bind free occurrences ofxin that expression. For example,dx²/dxis best understood asd/dx (x²). The notation would be clear if you implement calculus in a program.If not fraction, why fraction shaped?
If you use exterior calculus notation, with d = exterior derivative, everything makes so much more sense
I just think of the definition of a derivative.
dis just an infinitesimally small delta. Sody/dxis literally justlim (∆ -> 0) ∆y/∆x. which is the same aslim (x_1 -> x_0) [f(x_0) - f(x_1)] / [x_0 - x_1].Note:
∆ -> 0isn’t standard notation. But writing∆x -> 0requires another step of thinking:y = f(x)therefore∆y = ∆f(x) = f(x + ∆x) - f(x)so you only need∆xapproaching zero. But I prefer thinkingd = lim (∆ -> 0) ∆.
Wait bottom mathematican is using j=√-1 instead of i and not the engineer? Because I’m EE gang, and all my homies use j.
[Lapsed] mechanical engineering gang checking in. I was also surprised. Though, tbh, I think it came down to personal preference of the professor more than field-wide consensus.
That part also got me really confused. All the mathematicans I know use i while engineers use i or j depending on the kind of engineer. I’ve never seen a Pikachu engineer using anything other than j.
Pikachu engineer
That’s a fucking favorite now. Keeping that in my back pocket.
OPs boyfriend is obviously an i engineer and hates j engineers. No one can stay angry at mathematicians - engineers on the other hand…
a real mathematician would use
(0, 1)instead ofiThe fun starts when you study quaternions
i^2 = j^2 = k^2 = ijk = −1This can’t be real
They’re actually very useful: https://en.wikipedia.org/wiki/Quaternion
(…I think you may have gotten whooshed…)
Hehe, maybe a little, but wanted to share just in case someone didn’t know :3
I clicked your link, I barely made it out of highschool so I have no idea what any of it means, but I like reading things I shouldn’t understand anyway, sometines it’s so interesting even without understanding.
So I thank you!
Quaternions are the closest we get to lovecraftian horror in real life.
Four dimensional and mostly imaginary, they were carved into a stone bridge by a crazy mathematician in a fit of madness, Lord Kelvin called them “unmixed evil”, and the Mad Hatter from Alice may have been inspired by them.
Also they have been a curiosity at best for a long time, despite the efforts of a
secretQuaternion Society, but they suddenly blew up in usefulness in modern times as they happen to be an easy and fast way for computers to describe rotations in 3D space, so they’re everywhere.Yeah, lovecraftian as shit.
this isn’t real
It gets worse actually. You can define a number system using any power of 2 amount of i-like units in a similar relationship to quaternions using the Cayley-Dickson construction
Fascinatingly, you lose some property of the algebra at each step. Quaternions aren’t commutative: ABC != CBA. Octonians aren’t associative: (AB)C != A(BC). Once you get into 16 i’s with subscripts, it really gets crazy.
(Also, I just got the joke. Damnit @HappyFrog@lemmy.blahaj.zone your serious answer threw me off!)
Hehe, yeah, the joke was too good :P
Maybe a bit too complex for its own good.
I agree. Clearly i is current. What is this i=√-1 nonsense.
Fake and gay.
No way the engineer corrects the mathematician for using j instead of i.
As an engineer I fully agree. Engineers¹ aren’t even able to do basic arithmetics. I even cannot count to 10.
¹ Except maybe Electrical engineers. They seem to be quite smart.
Electrical engineers are the ones that use j though (because i is used for current)
I am used for current
Having worked with electrical engineers, some of them are quite smart, the rest have lead poisoning.
Engineer here, I can definitely count to 10 tho
0 1 10
0 1 everything that comes after is simply summarizes as “many”
deleted by creator
10? That’s the name some put to 1e1, right?
The inner machinations of an electrical engineer is too complicated for me to understand, I think they might be thinking on a higher order to understand these circuits
Thats why I barely passed my electrical engineering class lol
Except maybe Electrical engineers.
Yup, I can count just fine to the 10th number in a zero-indexed counting system: black, brown, red, orange, yellow, green, blue, violet, gray, white.
The mathematician also used “operative” instead of, uh, something else, and “associative” instead of “commutative”
“operative” instead of, uh, something else
I think they meant “operand”. As in, in the way dy/dx can sometimes be treated as a fraction and dx treated as a value.
I think you mean operator. The operand is the target of an operator.
The operand is the target of an operator
Correct. Thus, dx is an operand. It’s a thing by which you multiply the rest of the equation (or, in the case of dy/dx, by which you divide the dy).
I’d say the $\int dx$ is the operator and the integrand is the operand.
You’re misunderstanding the post. Yes, the reality of maths is that the integral is an operator. But the post talks about how “dx can be treated as an [operand]”. And this is true, in many (but not all) circumstances.
∫(dy/dx)dx = ∫dy = y
Or the chain rule:
(dz/dy)(dy/dx) = dz/dx
In both of these cases, dx or dy behave like operands, since we can “cancel” them through division. This isn’t rigorous maths, but it’s a frequently-useful shorthand.
I do understand it differently, but I don’t think I misunderstood. I think what they meant is the physicist notation I’m (as a physicist) all too familiar with:
∫ f(x) dx = ∫ dx f(x)
In this case, because f(x) is the operand and ∫ dx the operator, it’s still uniquely defined.
How do we know it’s gay though? OP could be a girl (male)
Newfag.
(sorry! seemed like the appropriate 4chan reply)
Because it’s 4chan. And there are no women on the Internet on 4chan
Sure OP is a girl. Guy In Real Life
My thoughts exactly lol
Right? They got that shit backwards. Op is a fraud. i is used in pure math, j is used in engineering.
That’s hilarious. You’re not seeing what’s going on backwards just like that (as I point at the point going nowhere shitty) in an equation that is finding as many clAEver ways to say something you actually not caring about talking about.
That’s like, "How many time van express the only thing that van’t be done until the 'verse itself tries to do what can’t be done and sever your…
…Oh, I see…you don’t have ([of course, because you can’t have to give {is}) nothing)] to give.
Unable to sea time doesn’t mean we can’t see(k)ER the mAETh.ac(k).cc(k).08
The only thin(g):(k) that doesn’t ever be never, is not at alla hack(g)in(g).G your lackthereof to divi…
Is this a copypasta or are you having a stroke?
Wah, wah, wah…
Not my problem.
Keep trying. /s
Learned a new word, Hate ****
Hate ****
I too take hate shits on the toilet.
Anger bang
Better plot than 50 Shades of Grey
hehe plot. getit? math and graphs and shit
Lmfao kill yourself
Relationship goals
I love how that wannabe 4chan nerd just got outnerded in the comment section
Why are we still visiting literal pro-Nazi websites?
4chan is a largely fascist website but that doesn’t mean every single screenshot is fascist or does something to promote it
It normalizes their behavior instead of shunning it. Remember: If there’s one Nazi at the bar who hasn’t been kicked out, you’re at a Nazi bar.
Doesn’t Lemmy have a ton of tankies on some instances?
If it’s fine because it’s a different instance, doesn’t that apply to different 4chan boards?
This was the reply that really made me think twice about my position.
There is a nazi at the bar (4chan) but also there’s a gay couple at the bar (the OOP). the gay couple leaves that bar and goes to another bar (Lemmy). is the second bar and its bargoers now also Nazis?
$\int dx f(x)$ is standard notation for physicists
But the post says before the integral, so I understand what they did would be $dx \int f(x)$, which is disgusting
NGL, this is hot.
I’m a mechanical engineering student with a math minor and I’m a switch so yeah, I’d take either side of this
