If $A=\begin{bmatrix} 1 & 1 & 2 \ 1 & 3 & 4 \ 1 & -1 & 3 \end{bmatrix}$, $B=adjA$ and $C=3A$, then $\frac{|adjB|}{|C|}$ is equal to

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Aicharya · Accepted Answer

Here's the corrected text with proper LaTeX formatting: $|A| = \begin{bmatrix} 1 & 1 & 2 \ 1 & 3 & 4 \ 1 & -1 & 3 \end{bmatrix} = |9 + 4 - 1(3 - 4) + 2(-1 - 3)| = 13 + 1 - 8 = 6$ $|adj B| = |adj adj A| = |A|^{n-1} = |A|^4 = |36|^2$ $|C| = |3A| = 3^3 	imes 6$ $\frac{|adj B|}{|C|} = $\frac{36 	imes 36}{3^3 	imes 6}$ = 8$

If $A=\begin{bmatrix} 1 & 1 & 2 \\ 1 & 3 & 4 \\ 1 & -1 & 3 \end{bmatrix}$, $B=adjA$ and $C=3A$, then…

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