.If a diagonal matrix "`A=diag[-1,2,5]" `then value of `|A|` is

The inverse of a diagonal matrix is a:

Which of the following statements is incorrect for a square matrix A?(|A|!=0) (1) If A is a diagonal matrix then A^(-1) will also be (2) If A is a symmetric matrix then A^(-1) will also be a symmetric matrix (3) If A^(-1)=A rArr A is an idempotent matrix (4) If A^(-1)=A rArr A is an involutory matrix

If A is a non-diagonal involutory matrix, then

Square matrix and diagonal matrix

If A is a diagonal matrix of order 3xx3 is commutative with every square matrix or order 3xx3 under multiplication and tr(A)=12, then the value of |A|^(1/2) is

If A = diag (4, 2, 1) then det A is equal to

If a matrix A is both symmetric and skew- symmetric,then A is a diagonal matrix (b) A is a zero matrix (c) A is a scalar matrix (d) A is a square matrix

If the matrix A is both symmetric and skew symmetric,then (A) A is a diagonal matrix (B) A is a zero matrix (C) A is a square matrix (D) None of these

If A= diag (1,4,5) then A^(-1) is equal to