If A = bmatrix a & 1 & -1 \\ 0 & b & 4 \\ 4 & 4 & c bmatrix and abc = 12, b = 4a, then the value of |A(adjA)| is: Option 1: 28^3 Option 2: 12^3 Option 3: 28^2 Option 4: 48^2

The answer is '28^3'. View full solution:

Algebra > Matrices & Determinants

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If $A = \begin{bmatrix} a & 1 & -1 \\ 0 & b & 4 \\ 4 & 4 & c \end{bmatrix}$ and $abc = 12$, $b = 4a$, then the value of $|A(adjA)|$ is:

$28^3$

$12^3$

$28^2$

$48^2$

✅ Correct Option: 1

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