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Which one of the following matrices is an elementary matrix?

Options

  1. A[ array lll 1 & 0 & 0 0 & 0 & 0 0 & 0 & 1 array ]
  2. B[ array lll 1 & 5 & 0 0 & 1 & 0 0 & 0 & 1 array ]
  3. C[ array lll 0 & 2 & 0 1 & 0 & 0 0 & 0 & 1 array ]
  4. D[ array lll 1 & 0 & 0 0 & 1 & 0 0 & 5 & 2 array ]

Correct answer

B. [ array lll 1 & 5 & 0 0 & 1 & 0 0 & 0 & 1 array ]

Step-by-step solution

An elementary matrix has each diagonal element 1. So, option (B) is correct answer.

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