- The number of 3x3 matrices that can be formed by using 1 and -1 such that the product of elements in each row and column is -1.

Ans : 16

- If A = \lim_{n \to \infty}(\begin{matrix} 1 & \frac{x}{n} \\ \frac{-x}{n} & 1 \end{matrix})^n then |A| is

Ans : 1