• Mathematician Chat v. 3.999...
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[QUOTE=elevate;49494645]I'm kinda like the guy you responded to. I'm also a programmer, and I frequently find myself programming things that involve math. I'd like to make more sense of the books and papers I read because it all looks like gibberish to me. Thanks for the recommendation.[/QUOTE] math.stackexchange.com is also a great resource if you don't understand something. Just make sure you do your due diligence and search for an answer before you ask something, and try first so you can post what you have tried.
[QUOTE=MuffinZerg;49494282]Math guys, I need advice and guidance. I am on my 4th year of an electrical engineering degree. Just half a year and I will get my degree and sail into the real world. I have taken a calculus course, linear algebra, discrete mathematics, probability theory and applied statistics. I am mainly a programmer and math had helped me a lot in that field. I will certainly be a programmer when I graduate (because the degree is useless and I don't like it and I already have experience working as a coder etc). I feel like despite all the courses I don't understand math. I have been given an overview of many things, but forgot them all. I can tell which task falls into what department and where to search, but I feel like I need more. I am fascinated by numbers and I have always felt like math makes you see the world differently when you get it. You wouldn't believe how emotional I got when i learned about how probability theory is used in industry mass production every day. I also feel like a half-educated programmer because I don't know math. I sometimes fidgit where I shouldn't : get coordinates right on a 2d pane, working with vectors. So here comes my question: is it possible to properly self-educate myself in algebra, discrete mathematics and probability theory? If so, how long is it going to take? What online courses and books should be of help? Is it worth it at all or am I better off learning practical things now that I am 5 minutes from the struggle to earn a living? That's a lot of questions, thanks in advance[/QUOTE] This is what I am doing right now, I don't even go to college anymore, everything I do is study at home. Let's just say it's a lot harder if subject doesn't interests you, but if it does, you will learn faster than @ college. One important tip: *) Make youtube/khan academy videos play faster (like at 1.5x speed), this way you will 'get it faster', because you won't have time to loose your focus :v:
I think my class attendance at the start was like 95% and in my last year it was 20% :v: Really depends on the subject/professor though. Some classes were impossible without example exercises done by the professor themselves and stuff like that. Others basically followed the syllabus word for word. (also [I]fuck[/I] course content provided solely with slides)
[QUOTE=Fourier;49531443]This is what I am doing right now, I don't even go to college anymore, everything I do is study at home. Let's just say it's a lot harder if subject doesn't interests you, but if it does, you will learn faster than @ college. One important tip: *) Make youtube/khan academy videos play faster (like at 1.5x speed), this way you will 'get it faster', because you won't have time to loose your focus :v:[/QUOTE] The nice thing about late graduate/research-level material is, unlike undergraduate, you can often ignore a subject entirely if you don't like it. I think if I went into math research I'd want to do something very topology/geometry and algebra oriented. I will probably never need to understand forcing.
I'm in math research at the moment and tbh I don't find it rewarding. I think the problem is that a lot of the research topics have no direct applications so I don't feel particularly helpful to society.
To me math itself is mentally stimulating but things coming to real life (through applications) do feel more rewarding.
Does anyone have tips/breakthroughs or really nice resources for Statics of Rigid Bodies in Engineering Mechanics? Really troublesome subject.
[QUOTE=Rainboo;49560914]Does anyone have tips/breakthroughs or really nice resources for Statics of Rigid Bodies in Engineering Mechanics? Really troublesome subject.[/QUOTE] What are you stuck with? Your best resource is going to be really practicing everything you can, building a rigorous system for solving statics problems, and speaking to your professor as soon as possible.
[QUOTE=paindoc;49563807]What are you stuck with? Your best resource is going to be really practicing everything you can, building a rigorous system for solving statics problems, and speaking to your professor as soon as possible.[/QUOTE] We're pretty much in the introductory parts, like resultant of concurrent forces/parallel forces/non-concurrent forces, the principle of moments, couples, and equilibrium involving pretty much all the aforementioned concepts, up until method of joints/sections. My situation seems to be pretty bleak right now, since we have a really terrible professor who just writes crap/talks to himself without explaining and who's just really kinda lazy, especially when it comes to interacting with students, and I personally don't have a good foundation in the needed subjects (trigonometry, physics and so on) since the things that were taught to me didn't really stick around in my head. While I do remember some basic concepts (pythagorean theorem and force components), I no longer remember stuff like relations between angles and stuff so I end up being really sucky at analyzing problems/figures. What I'm looking for now is if there's some sort of really good set of tutorials I can follow, in either video or written form somewhere in the net, because all the books/academic papers really fuck around with my brain, as they use a lot of terminology from the get go, especially when it involves past math lessons that I've long forgotten. Any tips for problem solving would be greatly appreciated, and if you guys could share like, your "eureka!" moments for statics that would also be great, since I can't seem to find a breakthrough by just normally studying, and I can't rely on my instructor to help me with that.
[QUOTE=Rainboo;49560914]Does anyone have tips/breakthroughs or really nice resources for Statics of Rigid Bodies in Engineering Mechanics? Really troublesome subject.[/QUOTE] Yes, here homework for you: Assuming: You know what is speed, velocity, acceleration, Force, mass, time, Δtime. Do: - Read about Euler integration. - Read about Hookes Law - Implement the hooke law on 1D with Euler integration. You need two points - fixed point x_f and moving point/mass x_m. - Extend that Euler integration to 2D. You have now 2D points (of - speed,velocity,force,mass). - Add gravity to the formula. Assuming you mastered this, you can now simulate spring. That should make rigid-bodies more easier to understand. If you go further, you can simulate BOTH points, the moving mass and (previous known fixed point), second moving mass. Now you can add as many dots and links (connections) as you like and you can simulate non-rigid bodies (soft-body). [sp]But you need to replace Euler integration with something more stable, because if you don't, physics simulation will explode. Euler is not stable for physics[/sp]
Studying about banzhaf power index and fair splitting algorithms. I need it for exams. At first I felt resistance because "who the f*** needs this shit", but now I see it's quite cool.
I really hate how people word some problems in math. I was helping my sister with the problem [quote] Given: Sin(-t)=1/2 Evaluate: a) Sin(t) [/quote] We spent a few minutes putting various degrees and radians of sin(1/2) into the answer box and got all of the attempts wrong (she had limited attempts). She decided to guess the next problem which was evaluate Csc(t). She guessed 2 and got it right. Thats when we realized the answer was -1/2. :suicide:
I don't really see anything misleading or strange in the wording of that problem.
[QUOTE=JohnnyMo1;49661102]I don't really see anything misleading or strange in the wording of that problem.[/QUOTE] We interpreted it as evaluate Sin(-1/2) or Sin(1/2)
[QUOTE=mralexs;49661159]We interpreted it as evaluate Sin(-1/2) or Sin(1/2)[/QUOTE] I think that's kinda on you guys. The wording was pretty clear imo. In fact, there were only 2 words in the whole problem. The point was understanding that the sin function is odd. [editline]2nd February 2016[/editline] Look at what the first part says: sin(-t) = 1/2. The sine of minus something = 1/2. Then they want to know what the sin of something is. So it's "You know the value of this function t units away from 0, what's the value t units away from zero in the other direction?" Questions like that are standard (and pretty unambiguous) so I'd focus on improving your understanding of what is being asked rather than blaming the way it's being asked.
[QUOTE=JohnnyMo1;49661376]I think that's kinda on you guys. The wording was pretty clear imo. In fact, there were only 2 words in the whole problem. The point was understanding that the sin function is odd. [editline]2nd February 2016[/editline] Look at what the first part says: sin(-t) = 1/2. The sine of minus something = 1/2. Then they want to know what the sin of something is. So it's "You know the value of this function t units away from 0, what's the value t units away from zero in the other direction?" Questions like that are standard (and pretty unambiguous) so I'd focus on improving your understanding of what is being asked rather than blaming the way it's being asked.[/QUOTE] Agreed. I really need to get better at these kind of things being in Calculus now
I recently took a Discrete Mathematics/Discrete Structures course and I found it to be one of the most enjoyable courses I have ever taken. It has strengthened my interest in mathematics in general. Does anyone here love Discrete Mathematics as much as I do? I especially enjoyed propositional logic, the basic proofs that we took (we took several proof methods) and boolean algebra. Discrete probability was my least favourite part, but I enjoyed it, as well. I am quite excited to learn more! :)
[QUOTE=Reflex F.N.;49667702]I recently took a Discrete Mathematics/Discrete Structures course and I found it to be one of the most enjoyable courses I have ever taken. It has strengthened my interest in mathematics in general. Does anyone here love Discrete Mathematics as much as I do? I especially enjoyed propositional logic, the basic proofs that we took (we took several proof methods) and boolean algebra. Discrete probability was my least favourite part, but I enjoyed it, as well. I am quite excited to learn more! :)[/QUOTE] Good to see a fellow Discrete enthusiast! Discrete is what sold me on studying maths further. The fundamentals are a lot of fun which is why I always ask to tutor them at my university. High level discrete maths gets a bit gross though. When I hit the unholy union of abstract algebra and number theory I decided to get into probability instead.
(9.5 * 10^n, 10 * 10^n), where n > 0 is the only range of numbers which, when any member is multiplied by 2, the digit found at n+1 also begins with 9 i.e: 196 = (1 * 10 ^2) + (9 * 10^1) + (6 * 10^0) = (1 * 10 ^2) + (9.6 * 10^1) so n = 1, and the n+1 digit is 9. 196 * 2 = 392 = (3 * 10^2) + (9 * 10^1) + (2 * 10^0) the n+1 digit is also 9. second digit in both is 9
[QUOTE=Reflex F.N.;49667702]I recently took a Discrete Mathematics/Discrete Structures course and I found it to be one of the most enjoyable courses I have ever taken. It has strengthened my interest in mathematics in general. Does anyone here love Discrete Mathematics as much as I do? I especially enjoyed propositional logic, the basic proofs that we took (we took several proof methods) and boolean algebra. Discrete probability was my least favourite part, but I enjoyed it, as well. I am quite excited to learn more! :)[/QUOTE] Dunno, I am totally the opposite, I have such difficulties with it that I don't know where to start. It is true though that (right now) I try to learn 6 months worth of lectures in 4 days. [editline]7th February 2016[/editline] (althrough I do like many aspects of it, its math anyway)
What are some fun thing I can do with math? I admit I am waay below the ability to do cool stuff like physics or something like that. The furthest I got is basic algebra.
[QUOTE=Daysofwinter;49723136]What are some fun thing I can do with math? I admit I am waay below the ability to do cool stuff like physics or something like that. The furthest I got is basic algebra.[/QUOTE] How basic? I started learning a little relativity before I got to calculus. I'd credit that with a lot of my ability to do math now, since it was really interesting and made me want to learn more.
[QUOTE=JohnnyMo1;49723448]How basic? I started learning a little relativity before I got to calculus. I'd credit that with a lot of my ability to do math now, since it was really interesting and made me want to learn more.[/QUOTE] Is there a way to test my abilities now beyond khan academy?
Write everything you know and write everything you know that you don't know.
Or just do exercises from the relevant subject? I'm sure there are general high school maths books that have tons of solved exercises.
[url=https://cloud.sagemath.com]SageMathCloud[/url] is the shit. Sage is wonderful but having to dick around with a virtual machine or whatever sucks. I feel like I do everything productive server-side nowadays. ShareLaTeX, DataJoy, SageMathCloud. It's great. I can type up my homework anywhere I have computer access.
[QUOTE=JohnnyMo1;49739718][url=https://cloud.sagemath.com]SageMathCloud[/url] is the shit. Sage is wonderful but having to dick around with a virtual machine or whatever sucks. I feel like I do everything productive server-side nowadays. ShareLaTeX, DataJoy, SageMathCloud. It's great. I can type up my homework anywhere I have computer access.[/QUOTE] The cloud really is the future, for better or worse. Can't wait until I can start taking my upper division math courses :D being a math major is awesome.
[QUOTE=Yozora_Mikazu;49771156]The cloud really is the future, for better or worse. Can't wait until I can start taking my upper division math courses :D being a math major is awesome.[/QUOTE] Upper division and grad level courses are really fun. Learnong just how flexible math can be is really interesting. Seeing how the topological definition of continuity reproduces your old definitions and generalizes more easily. Seeing how representing conics with polynomials gets subsumed by varieties, and then varieties get further subsumed by schemes. The abstraction is fascinating.
Just had my first probability exam yesterday. I did a bit shit on it I think. It's just that I lack the intuition for some problems... which is odd, because I remember getting the same feeling when looking at O.D.E. problems, but I quickly got used to it. But I still apparently haven't gotten used to probability problems. One example is: [quote]You set three alarm clocks to wake you up in the morning. The probability of them ringing is 0.8, 0.9, and 0.95. A) What is the probability that you wake up in the morning? B) What is the probability that exactly two alarm clocks will ring?[/quote] I just don't know where to begin with this. I know the formulas we have available (Baye's formula, law of total probability seem relevant here) but I simply do not know what to do.
For A) at least you can calculate the complementary event which is that none of the alarms ring and subtract that from 1. So P(You wake up) = 1 - P(None of the alarms ring) = 1 -(0.2 * 0.1 * 0.05) = 1 - 0.001 = 0.999
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