Khan Academy: Linear Algebra: Visualizations of Left Nullspace and Rowspace

Video builds upon the column spaces and null spaces of the 2x3 matrix and its transpose found in the previous video. Uses them to explain some relationships between the four fundamental subspaces, namely that the orthogonal complement of the column space of a matrix is the left null space of the matrix, any member of the row space is orthogonal to any member of the null space, and the left null space of the transpose of a matrix is orthogonal to the column space of the transpose of the matrix. [19:50]