Question
Choose the correct answer from the given four options.For any two matrices A and B, we have:
  1. $\text{AB}=\text{BA}$
  2. $\text{AB}\neq\text{BA}$
  3. $\text{AB}=\text{O}$
  4. None of the above.

Answer

  1. None of the above.
Solution:
For any two matrices A and S, we may have AB = BA = I, $\text{AB}\neq\text{BA}$ and AB = O but it is not always true.

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