Which of the following statements are correct? (A) If A is a square matrix, then $|A^2|=|A|^2$. Choose the correct answer from the options given below: |
(A), (B) and (D) only (A), (B) and (C) only (A) and (D) only (B), (C) and (D) only |
(A) and (D) only |
The correct answer is Option (3) → (A) and (D) only Check each statement: (A) If $A$ is square, $|A^2| = |A|^2 ✅$ (True) (B) For square matrices, $\det(AB) = \det(A) \cdot \det(B) ❌$ (False, not sum) (C) $A$ is order 3, $|A| = 2$, then $|-3A| = (-3)^3 |A| = -27*2 = -54 ❌$ (D) Matrix $\begin{bmatrix} 5-x & x-1 \\ 3 & 5 \end{bmatrix}$ is singular → determinant = 0 Determinant: $(5-x)(5) - (x-1)(3) = 25 - 5x - 3x + 3 = 28 - 8x = 0$ $x = \frac{28}{8} = \frac{7}{2} ✅$ |