# Search results

1. ### Lubrication - is fine machine oil better ?

Lubrication -- is fine machine oil "better"? So there is always a debate on gun forums over if lubricants marked for firearms are better then motor oil or cheaper automotive lubricants. I'm curious if anyone here has any hard information on the differences and what is better?
2. ### Axiom of Choice and Metric Spaces.

So the axiom of choice is confusing to me, apperently there is a distinction between the exsistence of an element and the actual selection of an element? I'm confused as to how much the axiom of choice is needed in elementary metric space theorems? As an example, is the Axiom of Choice needed...
3. ### Taylor series expansion of a power series.

If f(x) is a power series on S = (a-r, a+r), we should be able to expand f(x) as a taylor series about any point b within S with radius of convergence min(|b-(a-r)|, |b - (a + r)|) Does anyone have a proof of this or a link to a proof? I have seen it proved using complex analysis, but I...
4. ### Math Jobs for those with a masters/phd in Applied Mathematics

What are my job options if I got a masters or PhD in applied mathematics? I have no interest in teaching.
5. ### Complex line integral

I read(and numerically calculated) that the line integral around a circle of radius r centered at 0 for the function conjugate(z)/(z - t) is 0 for all t inside the circle. I don't know see how this integration is performed.
6. ### Directional Derivatives, Complex Variables and the exsistence of a complex derivative

I'm not sure if it's OK to post this question here or not, the Calculus and Beyond section doesn't really look very heavily proof oriented. I'm trying to prove that if continuous complex valued function f(z) is such that the directional derivatives(using numbers with unit length) preserve...
7. ### A problem with the Axiomatic Foundations of Mathematics

After looking at the axiomatic systems of modern mathematics and asking myself what proves they are self consistent I went looking for an explanation and so far I have found only that they have not been proven self consistent nor likely will a proof ever exist. So the possibility of a...
8. ### ODE Theory books

I hope this OK to do, I posted the same question in the science book section and have not gotten a response(admittedly I haven't waited very long but I am sort of in a rush and it doesn't seem to be a question which comes up often). I would like to purchase a book on ODE theory(as in it gives...
9. ### Applied algebra?

I hope this is appropriate as it is related to algebra but if it is not I pre-apologize. I was wondering if someone would give examples of algebra being used in interesting ways, either in direct applications or applied to subjects which interest me(analysis/differential equations/dynamical...
10. ### Construction of Real Numbers.

I was looking at the construction of the real number system. I know dedekind cuts can be used(completely worthless in terms of understanding I think) and Cauchy sequences can be used (I wish my analysis book used them) but I would like to see a construction based on infinite decimal...
11. ### Mathematics to MS in EE?

I was wondering if it was possible to go from a BS in mathematics to a MS in EE and skip the BS in EE altogether? I was interested in a double major of EE and Mathematics but I'm wondering if its really needed to get a BS in EE to do a MS in EE?
12. ### Applications of abstract algebra to engineering

I was wondering if there are any applications of abstract algebra to engineering and where I can go to learn about them?
13. ### Dual Masters?

I was wondering if anyone thinks it possible to do two masters degrees? Perhaps not at once but staggered by a year? I was thinking of a masters in engineering and applied mathematics.
14. ### Schools Retaking courses at different universities.

I am currently at a university and will be moving to another, the university that I am at has a really poor analysis sequence(due to the teacher being incompetent at teaching). I am wondering if it's detrimental to me to take the analysis sequence at my current university since I almost...
15. ### Complex Analysis

I don't think this is the right area to post this question so to the mods: please be kind and move it to a better section if one exists. I'm looking for a textbook on complex analysis which gives proofs but is accessible without a formal real analysis course. I would appreciate suggestions...
16. ### Lagrange Multipliers

I have been reading about Lagrange Multipliers, my book along with wiki and other resources I have read use an intuitive argument on why the max/min contour lines end up tangent to the constraint equation. I don't really understand it, especially considering the obvious flaw as shown by the...
17. ### Engineering Physics ?

"Engineering Physics"? So currently I been planning on specifying my major as Electrical Engineering, but mechanical has my interest too along with physics. I thought about a degree in physics but it has a lot of liberal arts baggage attached to it and is not offered at the engineering...
18. ### Discontinuous driving function

I have been studying LaPlace Transforms and I have learned how they are used to solve DE's with discontinuous driving functions, which is certainly interesting but I was wondering is it possible to solve the same DE's using other methods such as Undetermined Coefficients or Variation of...
19. ### Taylor Series Remainder

Hello, I was wondering if anyone could explain to me the thought process behind how you find the maximum remainder of a Taylor series? I read the wiki article and didn't help me at all, http://en.wikipedia.org/wiki/Taylor's_theorem My book talks about something like this(image is...
20. ### Question on ODE's with roots of multiplicity.

I was wondering how the general formula for the solutions of an nth order linear homogeneous ODE that had a characteristic equation which could be factored to (x-a)^n was derived(IE a set of solutions consisting e^(mx), x*e^(mx), ....x^(n-1)e^(mx)))? For example the ODE, y^(3)- 3y'' +...
21. ### First Order Autonomus ODEs

Could someone explain why the graph of a solution can never cross a critical point?
22. ### Book Recommendations?

Hello. I would like recommendations for a couple books. One which covers introductory number theory, algebra - etc(these looked interesting, I'm not sure which would be best but the "fundamental concepts of algebra" looked pretty good on goggle books -...