Mathematics · 2019
JEE Main · 12 April 2019, Shift 1 · Q65
If A is a symmetric matrix and B is a skew-symmetric matrix such that A+B= [2, 3; 5, -1], then A B is equal to:
If A is a symmetric matrix and B is a skew-symmetric matrix such that
$\displaystyle A+B=\left[\begin{array}{cc}2 & 3 \\ 5 & -1\end{array}\right]$, then $\displaystyle A B$ is equal to :
Official answer
(3)
$\displaystyle \left[\begin{array}{cc}
4 & -2 \\
-1 & -4
\end{array}\right]$
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JEE Main 2019 Mathematics question, with the answer from NTA’s final answer key. Where our answers come from.