Page 397 - Elementary_Linear_Algebra_with_Applications_Anton__9_edition
P. 397

(12)

which, by the linear independence of                         , implies that

Proof of Theorem 5.4.4b Assume that                          is a set of vectors in V, and to be specific, suppose that is a linear

combination of           , say

                                                                                                                                 (13)

We want to show that if is removed from S, then the remaining set of vectors                    still

spans span(S); that is, we must show that every vector w in span(S) is expressible as a linear

combination of                  . But if w is in span(S), then w is expressible in the form

or, on substituting 13,

which expresses as a linear combination of                   .

Exercise Set 5.4

        Click here for Just Ask!

   Explain why the following sets of vectors are not bases for the indicated vector spaces. (Solve this problem by inspection.)
1.

       (a)

       (b)

       (c)

       (d)

       Which of the following sets of vectors are bases for
2.

           (a) (2, 1), (3, 0)

           (b) (4, 1), (−7, −8)
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