Recent content by Shawj02

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    Mathematica Mathetica function (help fix my equation please)

    Yep, you're right! I've got it working perfectly now! My other question is: How do I write the ABS and REALS in LATEX? (so I can post things on physics forms better) so far I've got: \sum _{j=1}^z (-1)^j x_{j-1}-\sum _{j=6}^z 1+n_0 (-1)^z
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    Mathematica Mathetica function (help fix my equation please)

    I been playing around with the LATEX thing.. using Mathematica's right click and "copy as Latex" function. I have attached a copy of my original equation, below is an attempt to convert it into Latex. \sum _{z=1}^z (-1)^z x_{z-1}-\sum _{z=6}^z 1+n_0 (-1)^z There seems to be a...
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    Mathematica Mathetica function (help fix my equation please)

    Hi guys, I have a problem with Mathematica. The equation (see attachment) is SUPPOSE TO give: n[0]=n0 n[1]=x0-n0 n[2]=x1-x0+n0 n[3]=x2-x1+x0-n0 n[4]=x3-x2+x1-x0+n0 n[5]=x4-x3+x2-x1+x0-n0 n[6]=x5-x4+x3-x2+x1-x0+n0-1 ... But when I put in n[1] I get the following errors and output: Sum::itraw...
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    Kinetic Energy of 3D Fermi Gas at Absolute Zero

    ahhk, yeah that works. you could have explained it more but I got it in the end. I'll fill in the gaps for anyone else who might look at this in the future. use Ef=((khbar)^2)/2m to get the it to look right. and the big integral, you need to know that f(E) = 0 for E>Ef and f(E) = 1 for...
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    Wave length for a bragg diffraction from a incident x-ray.

    A cubic crystal with a lattice constant "a" is mounted with a [100] direction parallel to the incident x-ray beam. what would be the wave length for a bragg diffraction to occur from (110) and (111) planes? So Bragg's law is: 2d sin (theta) = n wavelength. So my thoughts are: This is...
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    Kinetic Energy of 3D Fermi Gas at Absolute Zero

    Show that the kinectic energy of a three-dimensional fermi gas of N free electrons at absolute zero is (Mathematica code used) u = 3/5 N Subscript[\[Epsilon], F] Now I know total energy of N particles is this integral u = \!\( \*SubsuperscriptBox[\(\[Integral]\), \(0\)...
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    Solving an example, vectors as rows or columns of a matrix = same solution.

    ahh, wait. i think I get it. solving for basis write 0,0,-5,3 4,7,-1,6 0,1,2,0 rearrange 4,7,-1,6 0,1,2,0 0,0,-5,3 Becomes 4,0,0,-33/5 0,1,0,6/5 0,0,-5,3 so a basis is (4,0,0,-33/5),(0,1,0,6/5),(0,0,-5,3)? And simplest (aka standard basis?) would look like...
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    Solving an example, vectors as rows or columns of a matrix = same solution.

    ok, so i'll try for the basis again. 0,4,0 0,7,1 -5,-1,2 3,6,0 switch column 1 and 2 around. 4,0,0 7,1,0 -1,2,-5 6,0,3 row reduce 4,0,0 0,1,0 0,0,-5 0,0,0 so a basis is {4,0,0,0},{0,1,0,0},{0,0,-5,0) or more simply {1,0,0,0},{0,1,0,0},{0,0,1,0}? So was that the only...
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    Solving an example, vectors as rows or columns of a matrix = same solution.

    One more thing... Ok, So from what I've read, If the vectors are written across a row like 4,7,-1,6 0,1,2,0 0,0,-5,3 Applying any operations (column wise) to this will not correspond to things that are meaningful in the original vector space, correct? The only useful information we can...
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    Solving an example, vectors as rows or columns of a matrix = same solution.

    x3 and x4, i meant collumns of the matrix (-1,2,5) and (6,0,3).
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    Solving an example, vectors as rows or columns of a matrix = same solution.

    Ok from other posts, everyone seems to say that it doesn't matter if you stick vectors into a matrix via columns or rows. So i want to prove this to myself using an example from my notes. The only problem is, I get different answers. Can someone correct me? from my notes it says "show (0...
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    Basic question, vectors into matrices

    Hi, My question is concerned with vectors, null space, solving for independence and subspaces. Now, I've found If a question gives a set of vectors and asks find if they are independent or not The vectors are written in columns (to make a matrix) and then Gaussian elimination is applied...
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    Inverse Laplace- Partial Fractions with exponential

    Im stuck in the same boat, but trying to get the partial fraction for "(e^[-s] -e^[-2s])/[(s^2)(s+1)]" I wasn't too sure what EngageEngage meant.
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    Normal approx binomial question.

    Ok, the question says Binomial with n=40. p=0.6 use normal approximation and determine.. a) value at 14. b)value lest then 12. So I thought I had this down and packed but the answer in the back of the book tells me otherwise. Anyways the following is my working. Y~Nor(13.5<x<14.5)...
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    Question with intersects and complements.

    Awesome. Yeah, I understand how. Just had a block a guess. Thanks.
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