The formula for the inverse of a 2x2 matrix is derived. (need tag for that formula)
Definition of the inverse of a matrix, examples, uniqueness; formula for the inverse of a 2x2 matrix; determinant of a 2x2 matrix; using the inverse to solve a system of linear equations.
Before we define the determinant of a matrix, we take a slight detour to introduce elementary matrices. These will bring us back to the beginning of the course and our old friend, row operations.
Pre-class quiz (four questions) on the matrix inverse to be completed by students after having watched a pre-class video on the topic.