Question

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 λⁿ, is a scalar, then adj(λA) = λ adj(A). 

(iv) A(adj A) = (adj A)A = |A|I

(a) Only (i) 

(b) (ii) and (iii) 

(c) (iii) and (iv) 

(d) (i), (ii) and (iv)

Answer 1

(d) (i), (ii) and (iv)