## Search found 159 matches

- Tue Oct 18, 2011 6:42 am UTC
- Forum: Mathematics
- Topic: dirac delta functions on TI 89
- Replies:
**7** - Views:
**5089**

### Re: dirac delta functions on TI 89

I realize this is the maths forum, but TI calculators are extremely nifty for physics type calculations. Anything with a few simple derivatives, integrals, maybe a linear system or some matrix manipulation gets sped up 10x. I'm pretty good with an 89 and I KNOW it helps me on exams when I can quickl...

- Tue Sep 27, 2011 3:20 am UTC
- Forum: Mathematics
- Topic: How legitimate is this?
- Replies:
**10** - Views:
**3109**

### How legitimate is this?

http://www.cs.nyu.edu/pipermail/fom/2011-September/015816.html It appears this guy is saying PA is inconsistent and ZFC might be inconsistent? And he is from Princeton so not some random crazy guy. This contains the actual meat of his argument but I'm pretty sure it's not complete yet: http://www.m...

- Wed Sep 07, 2011 11:04 pm UTC
- Forum: Mathematics
- Topic: An interesting topic for a math talk
- Replies:
**8** - Views:
**2127**

### Re: An interesting topic for a math talk

Talk about foundational set theory and how it was formulated. Hilberts problems, big picture stuff.

- Sat Jul 02, 2011 6:30 pm UTC
- Forum: Mathematics
- Topic: Calculating N-th digit of Pi
- Replies:
**5** - Views:
**2507**

### Re: Calculating N-th digit of Pi

The idea was that I could just copy their calculated digits, calculate one more, then I would have the most accurate version of pi known to mankind. Of course I'm not seriously trying to do this, I'm mostly curious about the computational efficiency of calculating the n-th digit.

- Sat Jul 02, 2011 5:23 pm UTC
- Forum: Mathematics
- Topic: Calculating N-th digit of Pi
- Replies:
**5** - Views:
**2507**

### Calculating N-th digit of Pi

It's my understanding if you really want to know a specific digit of pi, you can calculate that digit alone. So what is to stop me from beating the "most digits calcuated" records by calculating the 2 bazillionth and 1 digit with my laptop and then claiming the record for myself? I looked ...

- Fri Jun 24, 2011 7:49 pm UTC
- Forum: Mathematics
- Topic: How practical is a B.S. in Math?
- Replies:
**20** - Views:
**7760**

### Re: How practical is a B.S. in Math?

This thread is surprisingly relevant. I am currently going into my sophomore year with a Math major and CS/econ minor. Though I was thinking about switching that to a focus in Finance/Statistics, I'm not sure now. My math degree is technically something like "Applied Discrete/Computational"...

- Thu May 26, 2011 11:53 pm UTC
- Forum: Mathematics
- Topic: Interesting Problems?
- Replies:
**33** - Views:
**4733**

### Interesting Problems?

I was recently instructed to come up with an "interesting problem", in math, physics, economics...basically any field. I'm the biggest fan of math and the people involved know this, so I was thinking of interesting math problems to present. I am looking for problems that: - Require no more...

- Mon May 02, 2011 1:30 pm UTC
- Forum: Science
- Topic: I'm doing science, and I need test subjects.
- Replies:
**79** - Views:
**10778**

### Re: I'm doing science, and I need test subjects.

Your test only lists two options for respondents' genders. I considered adding an "other" option, but I figured those who don't consider themselves male or female comprise a very small portion of the population, and I'm probably not going to block by gender anyway. I don't expect it to bi...

- Mon Apr 11, 2011 4:45 am UTC
- Forum: Mathematics
- Topic: Getting my undergrad in math. How about you?
- Replies:
**51** - Views:
**8279**

### Getting my undergrad in math. How about you?

Hello everyone! Though I am not very active on these forums, I have been reading them for a few years now and I do appreciate all the help you've given me answering questions and providing some very enlightening discussion. I am currently a freshman in university and had been having huge troubles de...

- Mon Dec 06, 2010 1:37 am UTC
- Forum: Mathematics
- Topic: In Linear Algebra, should I use my calculator?
- Replies:
**12** - Views:
**2490**

### Re: In Linear Algebra, should I use my calculator?

I feel your pain with the row echelon stuff. I understand the process and the theory completely, but for some reason the practice/test problems my college gives are insanely complex to do by hand.I feel like I'm not really doing linear algebra, I'm doing 4th grade addition. Halfway through, you're a...

- Thu Dec 02, 2010 7:44 am UTC
- Forum: Mathematics
- Topic: Forbidden subwords -- logic vs intuition
- Replies:
**13** - Views:
**1857**

### Re: Forbidden subwords -- logic vs intuition

I do this with most math/physics things I learn. I try to understand them at an intuitive level, so that next time I have a new problem I can look at it quickly and understand what is going on. Sadly, sometimes it's hard to communicate this desire to "really understand" what I'm learning t...

- Fri Nov 12, 2010 9:02 pm UTC
- Forum: Mathematics
- Topic: How difficult is a Real Analysis class?
- Replies:
**79** - Views:
**20570**

### Re: How difficult is a Real Analysis class?

I'm a freshman in University right now (Virginia Tech). For us almost all serious math courses are limited to second year. I'm in engineering currently, but may go into CS or a pure math degree. The basics of calculus (I & II), sometimes multivariable, extremely elementary linear algebra, and In...

- Tue Oct 19, 2010 4:14 am UTC
- Forum: Mathematics
- Topic: Why are linear problems "Solvable"
- Replies:
**4** - Views:
**1424**

### Re: Why are linear problems "Solvable"

Well perhaps the reason we study those things you listed so much is because they are linear? If all springs exhibited crazy nonlinear motion, they probably would be studied only in specialized scenarios when necessary. Imagine fluid flow was suddenly very linear and easy to study. You'd be in here l...

- Mon Oct 11, 2010 1:53 pm UTC
- Forum: Science
- Topic: Finding the coefficient of friction using a pendulum
- Replies:
**15** - Views:
**3056**

### Re: Finding the coefficient of friction using a pendulum

I'm having trouble conceptualizing how to solve this problem. I have a pretty basic physics background (in fact I'm sitting in a basic mechanics class right now), but wouldn't it be impossible to determine? The net force on the box while it slides down the ramp could be due to a variety of things. W...

- Sun Oct 03, 2010 5:37 pm UTC
- Forum: Mathematics
- Topic: I join the blagosphere
- Replies:
**28** - Views:
**2904**

### Re: I join the blagosphere

Sounds pretty awesome? I read your first entry and it was extremely interesting. I have a background in Calculus and knew some general ideas about sets but the entry was very informative and easy to understand. I probably actually *gasp* learned something.

- Thu Sep 16, 2010 1:16 am UTC
- Forum: Science
- Topic: please help me with this.
- Replies:
**21** - Views:
**3738**

### Re: please help me with this.

Having been on this forum a full year now, it's interesting to see the rise/fall of homework related topics and the subjects within. If aliens were receiving transmissions of purely the xkcd science forum, I have no doubt they could construct the curriculum of earth's introductory physics courses.

- Thu Sep 16, 2010 1:13 am UTC
- Forum: Science
- Topic: Teaching myself Physics-- textbooks?
- Replies:
**10** - Views:
**2091**

### Re: Teaching myself Physics-- textbooks?

If you're a math major you're probably legit at math and would laugh at some introductory physics texts. The first book you listed is like most physics textbooks out there...it's designed for the average student that doesn't put much rigor into their arguments and problems. The Kleppner book on the ...

- Mon Sep 06, 2010 3:23 pm UTC
- Forum: School
- Topic: My school fails at computer security...
- Replies:
**314** - Views:
**116977**

### Re: My school fails at computer security...

I had a really hilarious experience with my school near the end of my senior year last year. Basically they called me in on two different things, one was "skipping school" at the end of the day of a field trip, and the other was going to facebook. Facebook is blocked on the computers, but ...

- Mon Sep 06, 2010 5:53 am UTC
- Forum: Mathematics
- Topic: What should I be getting out of these classes?
- Replies:
**2** - Views:
**649**

### What should I be getting out of these classes?

I'm currently enrolled in a Vector Geometry and Linear Algebra course as a freshman at college, and unfortunately both classes are online (though I'm free to get in-person help if I want it). I don't have a textbook for either, just some sorta sloppily put together online resources that don't really...

- Sun Aug 29, 2010 12:25 am UTC
- Forum: Science
- Topic: Advice on career choice
- Replies:
**21** - Views:
**3010**

### Re: Advice on career choice

Once again thank you guys for the responses. I think I'm getting a better picture of what my options are at this point. The other night we were required to attend an engineering lecture from a pretty well qualified guy, and I figured it was going to be boring as hell. What do you know, he works on t...

- Thu Aug 26, 2010 2:50 am UTC
- Forum: Science
- Topic: Advice on career choice
- Replies:
**21** - Views:
**3010**

### Re: Advice on career choice

In the last half hour I also encountered the combination of math/econ majors. That would be pretty cool, since I find both of those subjects interesting and from what I read they can be lucrative if you hit it right. Either way I just want to do something for the next 4 years and in the rest of my l...

- Thu Aug 26, 2010 1:41 am UTC
- Forum: Science
- Topic: Advice on career choice
- Replies:
**21** - Views:
**3010**

### Advice on career choice

Hello everyone. I know a lot of you are fairly well educated and can draw from experiences about what I'm asking, I've decided to post here rather than the school board. Basically my situation is this: I'm a freshman at Virginia Tech in the Engineering program (literally just started this week). I g...

- Sat Jul 03, 2010 5:24 am UTC
- Forum: School
- Topic: AP Lang: Taking the test without the class
- Replies:
**25** - Views:
**4050**

### Re: AP Lang: Taking the test without the class

Epic bump. Got my scores back and I ended up with a 4. I ended up doing 0 practice tests and just had a brief conversation with an AP Lang teacher the day before, so I went into it basically blind other than the test structure. I was concerned for awhile since I used some cursing and referenced some...

- Thu Jul 01, 2010 9:32 pm UTC
- Forum: Science
- Topic: Low occurence of Boron in the universe
- Replies:
**8** - Views:
**1535**

### Re: Low occurence of Boron in the universe

A note on the \alpha\beta\gamma paper. That was written by Gamow and his student, Alpher. Hans Bethe got added because Gamow was a notorious trickster, the Feynman of his generation, and he couldn't stand that gaping hole in the Greek alphabet :) Which as I understood it, really screwed Alpher over...

- Mon Jun 28, 2010 5:53 am UTC
- Forum: Mathematics
- Topic: Math pick-up lines.
- Replies:
**15** - Views:
**2824**

### Re: Math pick-up lines.

I can see where it would be an interesting topic if presented in the right way. It is a powerful symbol that can be seen to represent several of the most important branches of maths together and the pieces involved aren't really mind shattering. I'm talking about the individual expressions in the eq...

- Wed May 26, 2010 4:24 am UTC
- Forum: Individual XKCD Comic Threads
- Topic: 0745: "Dyslexics"
- Replies:
**143** - Views:
**48775**

### Re: "Dyslexics" Discussion

I'm probably just dumb, but where's the joke in this comic? I simply don't see any sort of punchline whatsoever. I'm going to assume you're being serious and possibly look like a prick-know-it-all-who-uses-too-many-hyphens there is a joke stating "Dyslexics of the world, untie" where it i...

- Fri May 21, 2010 3:33 am UTC
- Forum: Mathematics
- Topic: Question about infinite series
- Replies:
**9** - Views:
**1632**

### Re: Question about infinite series

I am in Calculus BC right now (or II, or whatever you want to call it it. High school calculus course part 2), and we learned about infinite series and sums and stuff earlier in the year, and I was wondering if the specific property I'm looking at has a name. Let me demonstrate. From what I can tel...

- Fri May 21, 2010 1:15 am UTC
- Forum: Mathematics
- Topic: Question about infinite series
- Replies:
**9** - Views:
**1632**

### Question about infinite series

I am in Calculus BC right now (or II, or whatever you want to call it it. High school calculus course part 2), and we learned about infinite series and sums and stuff earlier in the year, and I was wondering if the specific property I'm looking at has a name. Let me demonstrate. From what I can tell...

- Wed May 05, 2010 11:02 pm UTC
- Forum: Mathematics
- Topic: Largest [real] number, and smallest number greater than zero
- Replies:
**11** - Views:
**3078**

### Re: Largest [real] number, and smallest number greater than

1) The largest finite [real] number x is definied as the sum of all real numbers in the set of real numbers. How do you define a sum over an uncountable set? Even if you just sum over the natural numbers, it clearly doesn't converge and thus doesn't give you a finite number. I'll just point you to ...

### Re: GIS help

If i were you, I would just try going into the properties and "symbology" tab and fiddling with every option you see. This has become my general method of approach for most issues. I think I have some idea why you're having so many problems... I'm using ArcGIS, not sure what exactly that ...

- Tue Apr 27, 2010 4:17 am UTC
- Forum: School
- Topic: How badly will this hurt me?
- Replies:
**19** - Views:
**3802**

### Re: How badly will this hurt me?

You're a freshman, and if you're already making sure to get A's and B's, you'll be just fine throughout high school. The trick to HS is to get A's and B's your freshman/sophomore years, then you can slack off a little bit Junior or Senior year when you don't want to work as hard (or you can continue...

### Re: GIS help

I use GIS software in a brand new class at my high school, and I have to say this software is pretty damn annoying. It's useful when I'm not getting some sort of obscure syntax error, but most of the time there is some sort of minor problem like this that is close to impossible to fix. And for a pro...

- Sun Apr 25, 2010 7:26 pm UTC
- Forum: Science
- Topic: Explaining Magnetic Nonsense
- Replies:
**14** - Views:
**1733**

### Re: Explaining Magnetic Nonsense

I'm currently in an AP Physics class that doesn't do E&M and I'm trying to figure mathematically how fast the ball would fly off in that gauss rifle ruler demonstration. If I am correct, since electromagnetism is very similar to gravity in that it is an inverse square force, we could basically m...

- Thu Apr 22, 2010 2:55 am UTC
- Forum: Science
- Topic: So, quick question. (Earth stopped in its tracks)
- Replies:
**103** - Views:
**9118**

### Re: So, quick question.

Wow, something I can answer with some reasonable certainty. Gravity most definitely propagates at the speed of light, exactly. This was actually one of the major things the Newtonian view of gravity got wrong. They assumed back then that it simply propagated instantly (there is no good reason not to...

- Thu Apr 22, 2010 12:05 am UTC
- Forum: Science
- Topic: Colliding 2 Bodies (Physics)
- Replies:
**12** - Views:
**2037**

### Re: Colliding 2 Bodies (Physics)

Not sure how far I'm bumping this post, but we actually discussed this exact problem today in my AP Physics C class. The teacher attempted to solve it in front of us and stumped himself/said it was taking too much time and moved on. That got me curious though. We were attempting to do it through for...

- Fri Apr 16, 2010 12:17 am UTC
- Forum: Science
- Topic: Physics: conservation of energy question
- Replies:
**4** - Views:
**969**

### Re: Physics: conservation of energy question

This is a straight up forces problem. Conservation of energy or work don't enter into it. Your acceleration is going up the ramp (since the can is decelerating) and you want to know from that deceleration when velocity will equal 0. It can be done with Conservation of Energy though, and that's like...

- Sun Apr 11, 2010 9:56 pm UTC
- Forum: Mathematics
- Topic: Fundamental calculus?
- Replies:
**21** - Views:
**2888**

### Re: Fundamental calculus?

I like the limit definition better too, but I have never learned about the binomial theorem before now. I managed to work pretty good up till that step upon which I had to look up how to represent something like (x+y)^n appropriately. When would you usually learn this kind of thing? It seems pretty ...

- Fri Apr 09, 2010 3:06 pm UTC
- Forum: Mathematics
- Topic: Fundamental calculus?
- Replies:
**21** - Views:
**2888**

### Re: Fundamental calculus?

Thank you for all the helpful replies. I now realize that while what philip wrote was helpful, it doesn't help me actually derive integrals. I was wondering why x^2 ends up as x^3/3. So i'm going to try some stuff with limits and riemann sums here and see if I can get that on my own. I understand wh...

- Thu Apr 08, 2010 4:18 am UTC
- Forum: Mathematics
- Topic: Fundamental calculus?
- Replies:
**21** - Views:
**2888**

### Re: Fundamental calculus?

Thank you very much, that was actually a very good explanation. I think I already understood most individual parts of what you wrote, but the way you wrote them as one leading to the other helped very much. Is it bad that I can really only "get" proofs when they are explained similar to th...

- Thu Apr 08, 2010 3:10 am UTC
- Forum: Mathematics
- Topic: Fundamental calculus?
- Replies:
**21** - Views:
**2888**

### Re: Fundamental calculus?

I'm in Calc 2 so I'm very familiar with the fundamental theorem of calculus, but it doesn't really help me figure out how these ideas came to fruition. The example I picked was very simplistic but please don't get the idea that I just started with integrals, I'm asking these questions after 2 years ...