jee-main 2016 Q65

jee-main · India · 09apr Matrices Determinant and Rank Computation

If $A = \begin{bmatrix} 5a & -b \\ 3 & 2 \end{bmatrix}$ and $A$ adj $A = A A^T$, then $5a + b$ is equal to:
(1) $-1$
(2) $5$
(3) $4$
(4) $13$

If $A = \begin{bmatrix} 5a & -b \\ 3 & 2 \end{bmatrix}$ and $A$ adj $A = A A^T$, then $5a + b$ is equal to:\\
(1) $-1$\\
(2) $5$\\
(3) $4$\\
(4) $13$