Offline paper
Mathematics · 2016
JEE Main 2016 · 2016-04-03 Offline · Q64
If A = [5 a, -b; 3, 2] and A adj A = A A^T, then 5 a+b is equal to:
If $\displaystyle \mathrm{A}=\left[\begin{array}{cc}5 a & -b \\ 3 & 2\end{array}\right]$ and $\displaystyle \mathrm{A} \operatorname{adj} \mathrm{A}=\mathrm{A} \mathrm{A}^{\mathrm{T}}$, then $\displaystyle 5 a+b$ is equal to :
Official answer
(2)
$\displaystyle 5$
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