2 1 -2-2 Let C= and D= 3 -1 3 0 Find each matrix below. If a matrix is not defined, click on "Undefined". (a) DC = ☐ (b) CD = = 0 (c) c² = X 000 Undefined

(a) The matrix I=[1001] is called an _____ matrix. (b) If A is a 22 matrix, then AI= _____ and IA= _____. (c) If A and B are 22 matrices with AB=I , then B is the _____ of A.

Find ATA and AAT for the matrix below. What do you observe? A=[132461]

Take this test to review the material in Chapters 4 and 5. After you are finished, check your work against the answers in the back of the book. Write the third column of the matrix as a linear combination of the first two columns if possible. [102422751]