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JEE Mains · Maths · STD 12 - 3 and 4 . metrices and determinant
If \(A\) is a symmetric matrix and \(B\) is a skew-symmetrix matrix such that \(A + B = \left[ {\begin{array}{*{20}{c}}
2&3\\
5&{ - 1}
\end{array}} \right]\) , then \(AB\) is equal to
- A \(\left[ {\begin{array}{*{20}{c}}
4&{ - 2}\\
1&{ - 4}
\end{array}} \right]\) - B \(\left[ {\begin{array}{*{20}{c}}
4&{ - 2}\\
{ - 1}&{ - 4}
\end{array}} \right]\) - C \(\left[ {\begin{array}{*{20}{c}}
{ - 4}&2\\
1&4
\end{array}} \right]\) - D \(\left[ {\begin{array}{*{20}{c}}
{ - 4}&{ - 2}\\
{ - 1}&4
\end{array}} \right]\)
Answer & Solution
Correct Answer
(B) \(\left[ {\begin{array}{*{20}{c}}
4&{ - 2}\\
{ - 1}&{ - 4}
\end{array}} \right]\)
Step-by-step Solution
Detailed explanation
\(A = A',B = B'\) \(A + B = \left[ {\begin{array}{*{20}{c}} 2&3\\ 5&{ - 1} \end{array}} \right]\,\,\,\,\,\,\,\,....\left( 1 \right)\) \(A' + B' = \left[ {\begin{array}{*{20}{c}} 2&5\\ 3&{ - 1} \end{array}} \right]\,\,\,\)…
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