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A square matrix [a_ i j ] such that a_ i j =0 for i j and a_ i j =k where k is a constant for i=j is called :

Options

  1. Adiagonal matrix, but not scalar matrix
  2. Bscalar matrix
  3. Cunit matrix
  4. DNone of the above

Correct answer

B. scalar matrix

Step-by-step solution

In a scalar matrix, a_ i j = array lll 0 & for i j k & for i=j array . Example [ array lll 4 & 0 & 0 0 & 4 & 0 0 & 0 & 4 array ]

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