Science:Math Exam Resources/Courses/MATH152/April 2010/Question A 28/Statement

Circle all of the following statements that are true for all invertible matrices A, and all matrices B and C of the same size as A and all scalars r ≠ 0:

1. (AB)C = A(BC)
2. (A+B)(A-B) = A²-B²
3. A^TB^T = (AB)^T
4. (A^-1)^T = (A^T)^-1
5. (rA)^-1 = $\frac{1}{r}$A^-1