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If A= [ array ccc 1 & 1 & -1 2 & -3 & 4 3 & -2 & 3 array ] and B= [ array ccc -1 & -2 & -1 6 & 12 & 6 5 & 10 & 5 array ] then which of the following is/are correct? 1. A and B commute. 2. A B is a null matrix. Select the correct answer using the code given below:

Options

  1. A1 only
  2. B2 only
  3. CBoth 1 and 2
  4. DNeither 1 nor 2

Correct answer

B. 2 only

Step-by-step solution

aligned & A = [ array ccc 1 & 1 & -1 2 & -3 & 4 3 & -2 & 3 array ] ; B = [ array ccc -1 & -2 & -1 6 & 12 & 6 5 & 10 & 5 array ] & AB = [ array lll 0 & 0 & 0 0 & 0 & 0 0 & 0 & 0 array ] & BA = [ array ccc -8 & 7 & -10 48 & -42 & 60 40 & -35 & 50 array ] & as AB BA & So A and B are not commute. aligned

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