If `A` is non-diagonal involuntary matrix, then `A-I=O` b. `A+I=O` c. `A-I` is nonzero singular d. none of these

If A is a singular matrix, then adj A is a. singular b. non singular c. symmetric d. not defined

The inverse of a diagonal matrix is a. a diagonal matrix b. a skew symmetric matrix c. a symmetric matrix d. none of these

If A is a singular matrix, then adj A is a . Singular b . non singular c . symmetric d . not defined

If Z is an idempotent matrix, then (I+Z)^n I+2^n Z b. I+(2^n-1)Z c. I-(2^n-1)Z d. none of these

If for the matrix A ,\ A^3=I , then A^(-1)= (a) A^2 (b) A^3 (c) A (d) none of these

If A is an invertible symmetric matrix the A^-1 is A. a diagonal matrix B. symmetric C. skew symmetric D. none of these

If P is non-singular matrix, then value of adj(P^(-1)) in terms of P is (A) P/|P| (B) P|P| (C) P (D) none of these

If C is skew-symmetric matrix of order n and X isnxx1 column matrix, then X^T C X is a. singular b. non-singular c. invertible d. non invertible

If A is a non-singular matrix, prove that (a d j\ A)^(-1)=(a d j\ A^(-1)) .

If B is an idempotent matrix, and A=I-B , then a. A^2=A b. A^2=I c. A B=O d. B A=O