Let A and B be arbitrary 33 matrices State True or False for
Let A and B be arbitrary 3×3 matrices. State “True” or “False” for each of the following statements. You do not need to justify your answers.
(a) If |A| = 5, then A is invertible. (
b) If |AB| = 0, then at least one of |A| and |B| must be zero.
(c) If |A| = 0 and |B| = 0, then |A + B| = 0.
(d) If |A| = 0 and |B| = 0, then |AB| = 0.
(e) |3A| = 3|A|.
(f) | A| = |A|.
(g) |A3 | = |A| 3 .
(h) If every entry of A is positive, then |A| is positive.
(i) If every entry of A is an integer, then |A| is an integer.
(j) |A + B| |A| + |B|.
Solution
a) true
b) true
c) false
d) true
e) false
f) true
g) true
h) false
i) true
j) true
