Multiple choice

Which one of the following equation is a correct identity for arbitrary 3 x 3 real matrices P, Q and R?

  1. P(Q + R) = PQ + RP

  2. (P – Q)2 = P2 – 2PQ + Q2

  3. det (P + Q) = det P + det Q

  4. (P + Q)2 = P2 + PQ + QP + Q2

Reveal answer Fill a bubble to check yourself
D Correct answer
Explanation

Correct options is (4).