NullSpace

NullSpace[m] gives a list of vectors that forms a basis for the null space of the matrix m.

Examples

Find null space:

NullSpace[{{1, 2, 3}, {4, 5, 6}, {7, 8, 9}}]
(* {{1, -2, 1}} *)

Verify null space vector:

{{1, 2, 3}, {4, 5, 6}, {7, 8, 9}} . {1, -2, 1}
(* {0, 0, 0} *)

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