Find the inverse matrix of A.
-$$A = \left[ \begin{array} { l l l }
1 & 3 & 2 \
1 & 3 & 3 \
2 & 7 & 8
\end{array} \right]$$
A) $\left[ \begin{array} { r r r } - 3 & 10 & - 3 \ 2 & - 4 & 1 \ - 1 & 1 & 0 \end{array} \right]$
B) $\left[ \begin{array} { r r r } - 3 & 10 & - 3 \ 2 & - 4 & 0 \ - 1 & - 1 & 1 \end{array} \right]$
C) $\left[ \begin{array} { c c c } 1 & \frac { 1 } { 3 } & \frac { 1 } { 2 } \ 1 & \frac { 1 } { 3 } & \frac { 1 } { 3 } \ \frac { 1 } { 2 } & \frac { 1 } { 7 } & \frac { 1 } { 8 } \end{array} \right]$
D) $\left[ \begin{array} { l l l } - 1 & - 3 & - 2 \ - 1 & - 3 & - 3 \ - 2 & - 7 & - 8 \end{array} \right]$

Question

Find the inverse matrix of A.
-$$A = \left[ \begin{array} { l l l } 
1 & 3 & 2 \
1 & 3 & 3 \
2 & 7 & 8
\end{array} \right]$$
A) $\left[ \begin{array} { r r r } - 3 & 10 & - 3 \ 2 & - 4 & 1 \ - 1 & 1 & 0 \end{array} \right]$
B) $\left[ \begin{array} { r r r } - 3 & 10 & - 3 \ 2 & - 4 & 0 \ - 1 & - 1 & 1 \end{array} \right]$
C) $\left[ \begin{array} { c c c } 1 & \frac { 1 } { 3 } & \frac { 1 } { 2 } \ 1 & \frac { 1 } { 3 } & \frac { 1 } { 3 } \ \frac { 1 } { 2 } & \frac { 1 } { 7 } & \frac { 1 } { 8 } \end{array} \right]$
D) $\left[ \begin{array} { l l l } - 1 & - 3 & - 2 \ - 1 & - 3 & - 3 \ - 2 & - 7 & - 8 \end{array} \right]$

Quizplus · Accepted Answer

To find the inverse of matrix A, one must apply the formula for the inverse of a 3x3 matrix, which involves calculating the determinant of A and the matrix of cofactors. After performing these calculations, the correct inverse matrix matches option A.

Find the Inverse Matrix of A A=[132133278]A = \left[ \begin{array} { l l l } 1 & 3 & 2 \\1 & 3 & 3 \\2 & 7 & 8\end{array} \right]A=​112​337​238​​

Find the Inverse Matrix of A $A = \left[ \begin{array} { l l l } 1 & 3 & 2 \\1 & 3 & 3 \\2 & 7 & 8\end{array} \right]$