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is a basis for V, the vector can be written in the form

Since ,…, lie in the kernel of T, we have                       , so

Thus S spans the range of T.

Finally, we show that S is a linearly independent set and consequently forms a basis for the range of T. Suppose that some linear
combination of the vectors in S is zero; that is,

                                                                                                (2)

We must show that                . Since T is linear, 2 can be rewritten as

which says that                   is in the kernel of T. This vector can therefore be written as a linear combination of the
basis vectors      , say

Thus,

Since              is linearly independent, all of the k's are zero; in particular,  , which completes the proof.

Exercise Set 8.2

       Click here for Just Ask!

   Let             be the linear operator given by the formula
1.

Which of the following vectors are in ?

       (a)

       (b)

       (c)

       Let         be the linear operator in Exercise 1. Which of the following vectors are in
2.

           (a)

           (b)
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