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Let matrix B be the adjoint of a square matrix A,I be the identity matrix of same order as A . If k( 0) is the determinant of the matrix A , then what is AB equal to?

Options

  1. AI
  2. BkI
  3. Ck ^2 I
  4. D(1 / k) I

Correct answer

B. kI

Step-by-step solution

aligned & B = adj A , I = Identity matrix, | A |=k & AB = A ( adj A )=| A | I =k I . aligned

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