(a) Suppose A is a 3 x 3 matrix such that A Using theorems from the course, find the determinant of A-21 (b) Let A = [a b c] def 19 hi with real numbers a, b, c, d, e, f, g, h, i such that det(A) = 3. a b What is the determinant of B=d+2a e+2b f+2c ? 2g 2h 21 Give a justification for your answer.