Indicate whether the statement is true (T) or false (F).
Justify your answer.
(a) If
AB and BA are both defined, then A and B are
square matrices.
(b) If
AB + BA is defined, then A and B are square
matrices of the same size.
(c) If
B has a column of zeros, then so does AB if this
product is defined.
(d) If
B has a column of zeros, then so does BA if this
product is defined.
(e) The expressions tr
(ATA) and tr(AAT ) are defined for
every matrix
A.
(f ) If
u and v are row vectors, then uTv = u ・ v.
Justify your answer.
(a) If
AB and BA are both defined, then A and B are
square matrices.
(b) If
AB + BA is defined, then A and B are square
matrices of the same size.
(c) If
B has a column of zeros, then so does AB if this
product is defined.
(d) If
B has a column of zeros, then so does BA if this
product is defined.
(e) The expressions tr
(ATA) and tr(AAT ) are defined for
every matrix
A.
(f ) If
u and v are row vectors, then uTv = u ・ v.