Matrix

Understanding Matrix Determinant

The determinant has nothing to do with “equations”, it is a scalar.

The determinant is only applicable to square matrices, describing the volume of n n-dimensional vectors. For two dimensions, it is the area. A determinant of zero indicates that the matrix cannot span an n-dimensional space, at most n-1 dimensions, i.e., not full rank. So the volume is zero in n dimensions.

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Understanding Matrix Multiplication

Matrix multiplication has four cases, but essentially they are all vector operations.

  1. Vector dot product
  2. Matrix multiply vector (right multiply)
  3. Vector multiply matrix (left multiply)
  4. Matrix multiply matrix
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