Question

Suppose that B is a matrix whose third column is the sum of the first two columns,
the third column of AB is
a) The product of the first two columns of AB.
b) The product of the first column and the second row of A and B only.
c) The sum of the first two columns of AB.
d) None of the above.​

Answer 1

Answer:

c the sum of the first two columns of AB