If $A = \begin{bmatrix} 1 & 1 \\ 1 & 1 \end{bmatrix}$ and $\det(A^n - I) = 1 - \lambda^n$ for $n \in N$,then $\lambda$ is:

If $P$ and $Q$ are two non-zero square matrices of the same order such that the product $PQ = 0$,then ........

For any $3 \times 3$ matrix $M$,let $| M |$ denote the determinant of $M$. Let $E=\begin{bmatrix} 1 & 2 & 3 \\ 2 & 3 & 4 \\ 8 & 13 & 18 \end{bmatrix}$,$P=\begin{bmatrix} 1 & 0 & 0 \\ 0 & 0 & 1 \\ 0 & 1 & 0 \end{bmatrix}$ and $F=\begin{bmatrix} 1 & 3 & 2 \\ 8 & 18 & 13 \\ 2 & 4 & 3 \end{bmatrix}$. If $Q$ is a nonsingular matrix of order $3 \times 3$,then which of the following statements is (are) $TRUE$?
$(A)$ $F = PEP$ and $P^2 = I$
$(B)$ $| EQ + PFQ^{-1} | = | EQ | + | PFQ^{-1} |$
$(C)$ $|(EF)^3| > |EF|^2$
$(D)$ The sum of the diagonal entries of $P^{-1}EP + F$ is equal to the sum of the diagonal entries of $E + P^{-1}FP$

Let $A = \begin{bmatrix} 1 & 2 \\ -2 & -5 \end{bmatrix}$. Let $\alpha, \beta \in \mathbb{R}$ be such that $\alpha A^{2} + \beta A = 2I$. Then $\alpha + \beta$ is equal to -

Consider the following statements:
Statement $I$: If $A$ is a non-singular matrix, then $A^{-1}$ exists.
Statement $II$: If $A$ and $B$ are symmetric matrices of the same order, then $(AB - BA)$ is a skew-symmetric matrix.
Choose the correct option.

Let $A$ be a symmetric matrix and $B$ be a skew-symmetric matrix,such that $A - B = \begin{bmatrix} 1 & 2 \\ 3 & 4 \end{bmatrix}$. Then $|A|$ is: