1. If B-C = 0, what reasoning is used to show that B=C?
c) associativity
d) exactly 2 from above
e) all of a, b, c

2. If the product of two matrices equals the 0 matrix, then
a) one of the matrices has to equal the 0 matrix
b) both matrices have to equal the 0 matrix
c) neither a nor b

3. If A is a square matrix and Ax=b has infinite solutions for 1 vector b, then
a) A is not invertible and I have a good reason why
b) A is not invertible but I am unsure of why
c) A is invertible but I am unsure of why
d) A is invertible and I have a good reason why
e) There is no way to tell whether A is invertible without more information

4. If A is a matrix that is NOT square and Ax=b has infinite solutions for 1 vector b, then which best describes A:
a) Ax=b must always have infinite solutions
b) Ax=b can have 0, 1 or infinite solutions
c) Ax=b can have 0 or infinite solutions
d) Ax=b can have 1 or infinite solutions

5. Let T: x ---> Ax be given as a linear transformation arising from a square 2x2 matrix A. Assume that the set of all outputs b (from Ax=b) is a line. What can we deduce?
a) The columns of A do not span R2 and I can think of an example
b) The columns of A do not span R2 and I can not think of an example
c) A is onto R2
d) The columns of A do not span R2 and A is onto R2
e) None of the above statements are true