Recent content by chefobg57

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    A problem with basis and dimension

    Oh great! So can we say then that the dimension for P would be: (n^2 - n)/2? Thank you so much!
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    A problem with basis and dimension

    Thanks for pointing that out. For 2x2 matrices,1 element is necessary. For 3x3 matrices, 3 elements, for 4x4 - 6 elements, for 5x5 - 9 elements, for 6x6 it's 15 elements.. I am trying to come up with the proper function that will generate such output, given the input (n), but ... I can't...
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    A problem with basis and dimension

    Hm.. Well, I am debating between n and 2n numbers. The following 2x2 matrix is antisymmetric: 0 a -a 0 So, it depends on one number, a. A description of a 3x3 matrix would depend on 3 numbers, a, b, and c and so forth. Does this mean that this is the answer to the problem? n...
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    A problem with basis and dimension

    Hi! I am working on the following problem: If a matrix is antisymmetric (thus A^T = -A), show that P = {A \in R | A is antisymmetric} is a subset of Rnxn. Also, find the dimension of P. So far, I've proven that P is a subset of R and I am guessing that, in order for me to find the...
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    Idempotent matrix problem - HELP

    Hm.. Well, Ev = nAv => v = nAv .. Doesn't this mean that nA=1?
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    Idempotent matrix problem - HELP

    I checked my notes and as far as I understand you're talking about the invertible matrix theoremy... Can we then say that: Assuming that E-nA is not invertible means that there will be a non-zero vector x, such that (E-nA)x=0. However, this suggests that E-nA is not row equivalent to E which...
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    Idempotent matrix problem - HELP

    I am sorry, I am quite new to Linear Algebra I am not really sure what the answer to your question should be... Can you explain a little bit more why there should be a non-zero vector such that (E-nA)v=0? Thank you for helping me out! You're a life saver!
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    Idempotent matrix problem - HELP

    idempotent matrix problem - HELP :( Hi, I have the following problem with an idempotent matrix and I am stuck... If A is an idempotent (A^2 = A), is E - nA invertible /E is the identity matrix and n is a real number/ and why? I've tried with setting (E - nA)(E - nA) but it doesn't get me...
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