# Let A = [aij] and B = [bij] be two 3 ´ 3 real matrices such that bij = (3)(i + j – 2) aij, where i, j = 1, 2, 3. If the determinant of B is 81, then the determinant of A is:

Question:

Let $A=\left[a_{i j}\right]$ and $B=\left[b_{i j}\right]$ be two $3 \times 3$ real matrices such that $b_{i j}=(3)^{(i+j-2)} a_{i j}$, where $i, j=1,2,3$. If the determinant of $B$ is 81 , then the determinant of $A$ is:

1. $1 / 3$

2. 3

3. $1 / 81$

4. $1 / 9$

Correct Option: 4

JEE Main Previous Year 1 Question of JEE Main from Mathematics Matrices and Determinants chapter.
JEE Main Previous Year Jan. 7, 2020 (II)

Solution:

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