# Search results

1. ### Should I bother with this last chapter of my Linear Algebra text?

When I was a student, I barely had time to eat, let alone explore beyond what was required of us. Before finals: I think it is best if you focus on just the material for which you are responsible. Anything that distracts you from that task may hurt your mark. After finals: Go ahead and learn...
2. ### Why is there no Aerospace Engineering Forum?

I think many people consider Aerospace Engineering a specialized discipline of Mechanical Engineering, so most questions relating to aerospace are usually posted in the Mechanical Engineering forum. So far, there simply hasn't been enough activity/demand to justify creating a forum specifically...
3. ### Scientific Computing vs Applied Math at UMN

I don`t know for sure, but off the top of my head, I think the Scientific Computing option would be the more generic of the two and, therefore offer the most job possibilities. I suppose it depends on location, and industry you want to be in. The first thing that comes to mind when I think of...
4. ### Comp Sci Store values in an arbitrarily sized matrix C++

Since your problem, as-is, does not require you to save the numbers, I suppose your solution works okay. Glad to know you got it working. However, in most cases, the data is saved for additional work. In this case, a dynamic array would be used. One way of approaching this problem would be to...
5. ### Discrete Fourier Transform of Sine Function

Here is some sample data. I wanted to have the points at t = T/4 and t = 3T/4 included, so the motion was divided into 20 uniform intervals. T = 1 time unit. k = 0 t = 0.0 sin(2*PI/20*t) = 0.0 k = 1 t = 0.05 sin(2*PI/20*t) = 0.309016994374947 k = 2 t = 0.1...
6. ### Discrete Fourier Transform of Sine Function

(1) For a real function, g(x), the Fourier integral transform is defined by g(x) = \int_{0}^{\infty} A(\omega )cos(2\pi \omega x)d\omega - \int_{0}^{\infty} B(\omega )sin(2\pi \omega x)d\omega where A(\omega ) = 2 \int_{-\infty}^{\infty} g(x)cos(2\pi \omega x)dx and B(\omega ) = 2...
7. ### Linear algebra and applications to aerospace

One application that comes to mind quickly is the analysis of aeroelasticity and flutter. By forming the appropriate matrix, and computing its eigenvalues and eigenvectors, you can determine the modes of vibration, and its frequencies. I suppose that would fall under the general rubric of...
8. ### Not sure where else to ask this -- Can I teach myself Diff Eqs?

Yes, it is possible. In fact, as you may have noticed already, most university work is up to you anyhow. Sometimes you get a bad professor, sometimes you get a good professor, sometimes you get a professor who knows the material but can't teach, etc. Whatever, the situation, the onus is on you...
9. ### Is the Math/Science Taught at MIT, Caltech, etc. Harder?

I think the courses taught at "elite" universities are a lot harder, especially if the school promotes itself as a "research" school. The difference between a college and a university is that a college typically does not offer graduate courses. Since the heads of professors tend to be in their...
10. ### Engineering Mechanical Engineeringmajor with math minor?

If you really want to get into things electronic, perhaps one option would be to complete your Bachelor's Degree in Mechanical Engineering, and then find a way to do advanced degrees in Electrical Engineering. I recommend caution about switching fields halfway through your schooling, or picking...
11. ### A Large scale eigenvalue problem solver

It would also be helpful if you could take advantage of any special properties of the array. For example, are the array entries real or complex? Is the array symmetric or Hermitian? Is the array sparse? etc etc. Several routines are written to make the most of these features and provide faster...
12. ### Which calculator purely for algebra solver (with quadratics, cubics)

I am curious to see the equations you are solving. Can you post them here? On the 48GX, you can enter the value of x where you suspect a zero will be (see the attached image.) The arrows on the calculator can be used to move the cursor into this field, and then you can enter an initial guess...
13. ### Which calculator purely for algebra solver (with quadratics, cubics)

I have the HP 48GX too; have had it for over twenty years and am very happy with it. In fact, it is possible to compute all roots of a polynomial in a single transaction. You use the SOLVE application. The polynomial coefficients are entered as a vector. You then click "SOLVE", and all the...
14. ### Nth degree polynomial

There is a Master's Thesis (in PDF format) from Oxford University posted at the following link: http://eprints.maths.ox.ac.uk/16/1/mekwi.pdf I think it does a pretty good job providing a general overview (and easily readable) of the various iterative methods available for solving...
15. ### Math needed

During my four years as an undergraduate engineering student, I took many math courses: Calculus (several levels), Linear Algebra, Topology, Complex Variables, Differential Equations, Partial Differential Equations, Numerical Analysis, and more, and each of those courses required a book itself...
16. ### I really need a good linear algebra book!

Doesn't the course include a book recommendation? Where will the problem sets come from? If you buy one book, but the problem sets come from another, you will end up spending more money than you have to. My first Linear Algebra textbook was "Elementary Linear Algebra" by Stanley I...
17. ### Taking first course in linear algebra

Where are you going to take this first Linear Algebra course (i.e. - what school)? Most first-year Linear Algebra courses are very similar; they all cover the same material. However, if you are enrolled in an upcoming program at a college or university, why not just surf that school's website...
18. ### Best free software to make to do lists and get things organized?

Most Smartphones come with many options available too. For example, I use a Samsung Galaxy S3 and it comes with a Planner and Memo App pre-installed. If you don't like those, there are many other apps that can be downloaded and installed. Perhaps you could find one that has the features you...
19. ### Parabolic Two-Body Motion

Thanks for the info. Are you good with conic sections? I am investigating the transition from elliptical to parabolic motion and could certainly use as much help as I can get. I am presently stumped. Here is what I am doing: I am investigating elliptical motion at a particular time and...
20. ### Project PF Proliferation - Free Gold Membership!

Are the terms still the same: six months Gold Membership for a link on a site but permanent for a photo? Seems backwards. Flyers usually get torn down daily by janitorial staff, so the advertising is a lot more short-term. A link, on the other hand, is more long-term and can be checked daily...
21. ### Parabolic Two-Body Motion

I have been working with elliptical motion for a while, so am aware that when one body revolves around another in an elliptical orbit it sweeps out equal areas in equal times (measured from a focus). However, I am not sure if the same applies to parabolic motion. If, say, a comet approaches...
22. ### Stargazing Is it worth getting a telescope?

I second this advice. In fact, I have heard this advice given repeatedly from astronomers and in astronomy forums. If you are just starting to explore an interest in stargazing, buy a pair of binoculars. If your interest in stargazing does not grow, at least you won't have a one-purpose piece...
23. ### Need resources for solving nonlinear matrix equations

Hi, Kosh. That equation looks very similar to a Quadratic Programming problem: minimize F(x) = (1/2) xT[H]x + cT x + α . Except in your case you are trying to zero the function, not minimize it. I wonder if it could be turned into such a problem with a little...
24. ### Schools High School Math vs College Math?

In addition to being taught at a much higher level, college/university math courses are usually totally different subjects. High school laid the ground work for the material you will learn in college. In high school, I covered basic algebra, some trigonometric identities, logarithms, maybe a...
25. ### Help Solving a Quartic Polynomial

Excellent! Thank-you very much!
26. ### Help Solving a Quartic Polynomial

I am trying to solve an equation: arccos(Y) = arctan(Y), where Y = 1/x This turns into a quartic equation: x4 - x2 - 1 = 0 It looks simple enough to simplify further; however, I must be having a brain-fart because I can't do it. I'd like to avoid resorting to a numerical solution...
27. ### Maple The best software for math and physics?

I think most commercial products are pretty similar; as far as I am concerned, they all offer capabilities way beyond what I will ever need. Unless your requirements are extremely advanced or specialized, they would all cover most of your needs. And there is no best program; there is only the...
28. ### Sentence Structure/Style Question

I was always taught that important points are moved toward the end of a sentence. Like others have mentioned, the summary/conclusion should be at the end, because the last point made is the one you most want to stick in the reader's mind. This practice is also seen in German, French, etc. many...
29. ### Make a triangular matrix from a square matrix

You want the symbolic solution for the eigenvalues of a 12x12 matrix?! That would be a nightmare! As far as I know, the various methods of computing eigenvalues--QR Decomposition, Characteristic Polynomial, etc.--are all pretty complicated. Perhaps the solutions of a 3x3 matrix would be...
30. ### Is there a formula for this parabola?

Yes, it can be done. One way would be to form two equations in two unknowns. You know the general form of a parabola, so plug the points in and solve for the values. And if the parabola is symmetric around an axis it simplifies easier. Although, I don't think you can prove only one...