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Z = null(A)
Z = null(A) returns a list of vectors that form the basis for the null space of a matrix A. The product A*Z is zero. size(Z, 2) is the nullity of A. If A has full rank, Z is empty.
Find the basis for the null space and the nullity of the magic square of symbolic numbers. Verify that A*Z is zero:
A = sym(magic(4)); Z = null(A) nulllityOfA = size(Z, 2) A*Z
The results are:
Z =
-1
-3
3
1
nulllityOfA =
1
ans =
0
0
0
0Find the basis for the null space of the matrix B that has full rank:
B = sym(hilb(3)) Z = null(B)
The result is:
B = [ 1, 1/2, 1/3] [ 1/2, 1/3, 1/4] [ 1/3, 1/4, 1/5] Z = [ empty sym ]
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