MATH-UA 120 Lecture Notes - Lecture 9: Invertible Matrix, Identity Matrix, Determinant
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Inverse of 2 x 2 matrix a)formula: b)c) example: What follows are just the steps that happened to occur to me. Your calculations could easily look quite different. ) (5) now that the lefthand side of the doublewide contains the identity, the right- hand side contains the inverse. That is, the inverse matrix is the following: applications of matrix equations, determinants, cramer"s rule The determinant is equal to (2 * 3) (1 * 1) Determinant of an n x n matrix 1. Minor th th a) to find the minor, m , simply delete the i row and j column, and i j finding the determinant of the remaining matrix: cofactor, a i j. D y = | a r | |c s | noticed how in finding d , you simply replace the x column with the solution x finding d.
