Matrix Basics
Adjoint and Inverse of a Matrix
adj A = the transpose of the matrix of co-factors
The product of a matrix A and its adjoint is equal to the unit (identity) matrix multiplied by the determinant A. Let A be a square matrix, then (Adjoint A). A = A. (Adjoint A) = | A |. I
If A and B are two square matrices of the same order, such that AB = BA = I (I = unit matrix), then B is called the inverse of A, i.e., B = A–1, and A is the inverse of B.
Inverse of a matrix by using the adjoint matrix. A–1 = (adj A) / | A |
Principal Component Analysis (PCA)
Tensors