You show that transformation is linear, of course, by showing that thedefinitionof "linear transformation" holds:

Is ?

To write it as a matrix, find and . That will give you the two columns of the matrix.

This is easy! Think of it as where I is the identity matrix.2)Find ann x mmatrixAsuch thatAx= 3x, for allxinR^n. Note: x is a vector, I just didn't know how to put a vector arrow above it.

To see the LaTex code I used for these, click on each formula.Thanks