Matrix algebra Definition and 67 Threads

  1. P

    Solve X', X for Y: Matrix Algebra Help

    Find X if X' * X = (50, 300) (300, 1000) Then find Y if Y * X = (300, 2000) Problem is that when I try to solve for X (or X') first, I get three equations with four unknowns (a11, a12, a21, a22). Any help?
  2. B

    Matrix Algebra; Linear Dependece; 3 Vectors; In R^4

    Homework Statement You have 3 Vectors say v1,v2,v3 in R^4 meaning they each have 4 components. How do you determine if they are linearly dependent or independent? And usually how do you denote 4 components? I know everyone knows how to denote three components which is just x,y,z but idk what...
  3. C

    Resistance of Pure Metals: A Matrix Algebra Approach

    Homework Statement A range of metallic alloys are tested for electrical conductivity and give the following results for identically sized samples. 25% copper with 75% tin gave a reading of 0.0071 Ohms 65% copper with 35% cadmium gave a reading of 0.0049 Ohms 40% copper with 40% tin...
  4. T

    Matrix Algebra Find an inverse for I-A

    Suppose A^n=0 for some n>1. Find an inverse for I-A. I don't understand how to do this. It isn't homework, but I'm just studying.
  5. L

    Matrix Algebra Inverse Matrix Question

    Homework Statement If A is an nxn matrix such that A^3 = 0 (the zero matrix) then (I-A)^-1 = ...? A. not invertible B. I+A^2 C. I-A D. I+A E. I+A+A^2 Homework Equations The Attempt at a Solution I just don't know how to work out what the inverse of (I-A) is if I know A^3... how is this...
  6. D

    Vector is not a linear combination of two vectors [matrix algebra]

    Homework Statement Find a vector w in R3 such that w is not a linear combination of v1 and v2 Homework Equations v1 = [1;2;-1] v2=[2;-1;-2] The Attempt at a Solution my question is : does w need to be in the span of v1 and v2?? Could i just choose [1; 1; 1] as my w vector??
  7. I

    Proving A-1 = 3I - A for a Square Matrix A Satisfying A2 - 3A + I = 0

    1. Show that if a square matrix A satisfies A2 - 3A + I = 0, then A-1 = 3I - A 2. A-1A = I and A-1A = I and more that I can't think of 3. 3A = A2 + I A = (A2 + I)/3 ? This question is weird :o Anyone know how to do it?
  8. L

    What Is The Purpose Of Matrix Algebra?

    Well I'm going to be taking Matrix Algebra next semester, and I have no clue what it's for. Wikipedia wasn't too enlightening. What is the purpose of matrix algebra, and what is is commonly used for?
  9. B

    Matrix Algebra to decode a message

    Homework Statement Hey, I need to decode a message hidden in a Matrix as a practice activity, and I'm rather stuck. The alphabet key is starting from the letter A,numbered using first: a)Fibonacci Sequence b)Prime Numbers c)Counting Numbers d)No numbers higher than 27...
  10. M

    [Matrix Algebra] Special matrix, columns as a first order derivatives

    Homework Statement Let a_1,...,a_n be Real. Then define a 2n x 2n matrix A as follows. The following are the first 4 and the last 2 columns; note that the (2k) column equals (a_k)(derivative of the (2k-1) column A[,1] = a_1^(2n),a_1^(2n-1),a_1^(2n-2),...,a_1^(2), a_1 A[,2] =...
  11. B

    Need help to find my mistake in a simple proof of a matrix algebra proposition.

    Homework Statement Is the following true for matrices? Hypotesis: AB = AC A != 0(zero matrix) Thesis: B=C The Attempt at a Solution AB = AC AB - AC = 0(zero matrix) AB - AC = A(B-C) // using the following property: A(B+C) = AB + AC iff A is mn matrix and BC are np matrices...
  12. A

    Matrix algebra over finite fields

    Hi, We recently started analyzing linear machines using matrix algebra. Unfortunately, I haven't had much exposure to operating in finite fields aside from the extreme basics (i.e. the definitions of GF(P)). I can get matrix multiplication/addition, etc. just fine, but it's when finding the...
  13. J

    Solve for Eigenvalues in QFT using Matrix Algebra | Ryder's QFT p.44

    Homework Statement On page 44 of Ryder's QFT, near the bottom of the page, it says: Homework Equations Equation (2.94) is (\gamma^{\mu}p_{\mu} - m)\psi(p) = 0 The Attempt at a Solution Writing out all four components, and then taking the determinant and setting to zero, I get: m^4 - (E^2 -...
  14. J

    Solving Simple Matrix Algebra Homework Problem

    Homework Statement This is from Ryder's QFT book, second ed. page 37. At the bottom of the page it says that the commutation relations (eqn 2.68?) are satisfied by: K = \pm i\frac{\sigma}{2} However, I do not find this to be so. What am I missing? Homework Equations Here is one of the...
  15. B

    Matrix algebra - matrix equation

    A=(5, 4) I (1, 0) (4,6) (0,1) Those are matrix by the way. How do I show A^2=11A-18I? I know I'm overlooking something, but i don't know what. Any tips would be helpful
  16. Z

    Eigenvectors and using them in matrix algebra.

    Hi. Marix A= |1 1 0 | |0 2 0 | |2 1-1 | Has three eigenvectors [1,1,1]^T, [1,0,1]^T and [0,0,1]^T, By using this knowledge solve A^11. Ok, solving A^11 is rather easy with any decent calculator, or even with pen , paper and some time, but how on Earth I'm supposed to benefit...
  17. T

    Learning Matrix Algebra for Chemical Equations

    Can someone explain to me how to use matrix algebra, to form a chemical equation?
Back
Top