21. Let T be the linear transformation from R³ to R³ whose matrix with respect to the standard bases is

What is the value of (p, q, r)^Transpose for which

A

B

C

D

E

Solution: The answer is D.

The question is equivalent to solving

That is,

Solving by eliminating x we get

Since only one of the multiple-choice answers has a z component equal to 3, it folows that D is the answer.