Column Space and Nullspace -- Lecture 6. An explanation of vector spaces and subspaces. Especially the column space and nullspace of a matrix.
Gilbert Strang, 18.06 Linear Algebra, Spring 2005. (Massachusetts Institute of Technology: MIT OpenCourseWare), http://ocw.mit.edu (Accessed November 16, 2008). License: Creative Commons BY-NC-SA.
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