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Section 21.2 Terminology and notation
The following definitions all apply to an \(m \times n\) matrix.
- column space
the subspace of
\(\R^m\) formed by the span of the columns of the matrix
- row space
the subspace of
\(\R^n\) formed by the span of the rows of the matrix
- null space
the subspace of
\(\R^n\) formed by the solution set of the homogeneous system with that matrix as the coefficient matrix
- nullity
the dimension of the null space of the matrix
