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Let A= ( array ccc 1 & -1 & 1 2 & 1 & -3 1 & 1 & 1 array )(10) B= ( array ccc 4 & 2 & 2 -5 & 0 & 1 & -2 & 3 array ) . If B

Options

  1. A-2
  2. B5
  3. C2
  4. D-1

Correct answer

B. 5

Step-by-step solution

A B=I A(10 B)=10 I [ array ccc 1 & -1 & 1 2 & 1 & -3 1 & 1 & 1 array ] [ array ccc 4 & 2 & 2 -5 & 0 & 1 & -2 & 3 array ]= [ array ccc 10 & 0 & 5- 0 & 10 & -5 0 & 0 & 5+ array ]=10 [ array lll 1 & 0 & 0 0 & 1 & 0 0 & 0 & 1 array ] if =5 .

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