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Question
Choose the correct alternative:
Which of the following is/are correct?
(i) Adjoint of a symmetric matrix is also a symmetric matrix.
(ii) Adjoint of a diagonal matrix is also a diagonal matrix.
(iii) If A is a square matrix of order n and λ is a scalar, then adj(λA) = λn adj (A).
(iv) A(adj A) = (adj A)A = |A|I
Options
Only (i)
(ii) and (iii)
(iii) and (iv)
(i), (ii) and (iv)
Solution
(i), (ii) and (iv)
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