# If A is a symmetric matrix and B is a skew-symmetrix matrix such that A + B = 2 3 5 1 é ù ê ú ë û – , then AB is equal to :

Question:

If $\mathrm{A}$ is a symmetric matrix and $\mathrm{B}$ is a skew-symmetrix matrix such that $\mathrm{A}+\mathrm{B}=\left[\begin{array}{cc}2 & 3 \\ 5 & -1\end{array}\right]$, then $\mathrm{AB}$ is equal to :

1. $\left[\begin{array}{cc}-4 & -1 \\ -1 & 4\end{array}\right]$

2. $\left[\begin{array}{cc}4 & -2 \\ -1 & -4\end{array}\right]$

3. $\left[\begin{array}{ll}4 & -2 \\ 1 & -4\end{array}\right]$

4. $\left[\begin{array}{cc}-4 & 2 \\ 1 & 4\end{array}\right]$

Correct Option: 2

JEE Main Previous Year 1 Question of JEE Main from Mathematics Inverse Trigonometric Functions chapter.
JEE Main Previous Year April 12, 2019 (I)

Solution:

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