1.
Determine which matrix is the 3 × 3 identity matrix.
A.
B.
C.
D.
Hint
2.
If
, find
N
-1
.
A.
B.
C.
D.
Hint
3.
Determine whether the pair of matrices
are inverses.
A.
no, because fractions cannot be a part of an inverse
B.
yes, because
A
·
B
= I.
C.
yes, because each entry in the second matrix is the reciprocal of its corresponding entry in the first matrix.
D.
no, because
A
·
B
I
Hint
4.
In order for a matrix to have an inverse, what must be true?
A.
ad
–
bc
= 1
B.
ad
–
bc
0
C.
ad
–
bc
= 0
D.
ad
–
bc
1
Hint
5.
What is the 4 × 4 identity matrix?
A.
B.
C.
D.
Hint