Kernel (matrix)

In linear algebra, the kernel or null space (also nullspace) of a matrix A is the set of all vectors x for which Ax' = 0. The null space of a matrix with n columns is a  linear subspace of n-dimensional Euclidean space.The nullspace (or kernel) of the matrix A is exactly the same thing as the nullspace (or kernel) of the linear mapping defined by the matrix-vector multiplication , that is, the set of vectors that map to the zero vector.
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