Maths 2 End Term 3 Apr 2022 — Question 1

Select all that apply.

1. A

   Consider two matrices A and B. If both the matrix multiplications AB and BA are well-defined then A and B are square matrices.

2. B

   Consider two matrices A and B of order n. If A is not invertible, then AB is not invertible.

3. C

   Consider two matrices A and B of order n. If AB = B, then B = I, where I is the identity matrix of order n.

4. D

   There exists a 2 × 2 matrix A ≠ I such that A³ = I, where I is the identity matrix of order 2 × 2.