JEE MAIN - Mathematics (2025 - 3rd April Morning Shift - No. 20)
Explanation
To find the expression $|2 \operatorname{adj}(3 A \operatorname{adj}(2 A))|$, we break it down as follows:
Recognize that:
$ |2 \operatorname{adj}(3 A \operatorname{adj}(2 A))| = 2^3 |3A (\operatorname{adj}(2A))|^2 $
Apply properties of determinants:
$ = 2^3 (3^3)^2 |A|^2 \left|\operatorname{adj}(2A)\right|^2 $
Further simplify using $|\operatorname{adj}(B)| = |B|^{n-1}$ for a $3 \times 3$ matrix:
$ = 2^3 \cdot 3^6 \cdot 5^2 \cdot (|2A|^2)^2 $
Simplify $|2A|$:
$ = 2^3 \cdot 3^6 \cdot 5^2 \cdot (2^3)^4 \cdot |A|^4 $
Continue to simplify:
$ = 2^3 \cdot 3^6 \cdot 5^2 \cdot (2^3)^4 \cdot 5^4 $
Expand and combine powers:
$ = 2^{15} \cdot 3^6 \cdot 5^6 $
Therefore, $\alpha = 15$, $\beta = 6$, and $\gamma = 6$. So, $\alpha + \beta + \gamma = 15 + 6 + 6 = 27$.
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