18 a If B is any echelon form of A then the pivot columns of

18. a. If B is any echelon form of A, then the pivot columns of B form a basis for the column space of A. b. Row operations preserve the linear dependence relations among the rows of A. C. The dimension of the null space of A is the number of Columns of A that are not pivot columns. d. The row space of A^T the same as the column space of A.

Solution

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