1. Determinant of a matrix
  2. Difference between inverse matrix and identity matrix and what are they?
  3. Eigenvalues
  4. Unitary or orthonormal matrix
  5. Diagonal matrix
  6. How to compute matrices?

Thank you in advance for answering anyone of them.

  • Stuad^Dib@mindly.social
    3·
    1 year ago

    @meowmeowmeow
    5. A diagonal matrix is what it sounds like - all of the (nonzero) entries are on the diagonal, from the top left corner to the bottom right. Why do we care? All sorts of calculations are easier with diagonal matrices, which is great for lazy mathematicians and efficient programmers. Some matrices aren’t diagonal, but “diagonalizable,” meaning we can shuffle them around into a similar diagonal matrix by using their eigenvectors, which comes in quite handy.

    • Stuad^Dib@mindly.social
      3·
      1 year ago

      @meowmeowmeow
      6. I assume by this you mean “how to compute the product of two matrices?” If you mean something else, let me know. Basically, if we want to multiply two matrices A and B to get their product AB, we multiply every row of the matrix on the left with every column of the matrix on the right. I can’t really typeset matrices here, so hopefully the examples on this page are helpful:
      https://www.mathsisfun.com/algebra/matrix-multiplying.html