JEE Mains · Maths · STD 12 - 3 and 4 . metrices and determinant
If \(A\, = \,\left[ {\begin{array}{*{20}{c}}
1&2&x\\
3&{ - 1}&2
\end{array}} \right]\) and \(B\, = \,\left[ {\begin{array}{*{20}{c}}
y\\
x\\
1
\end{array}} \right]\) be such that \(AB\, = \,\left[ {\begin{array}{*{20}{c}}
6\\
8
\end{array}} \right],\) then
- A \(y = 2x\)
- B \(y = -2x\)
- C \(y = x\)
- D \(y = -x\)
Answer & Solution
Correct Answer
(A) \(y = 2x\)
Step-by-step Solution
Detailed explanation
Let \(A = \left[ {\begin{array}{*{20}{c}} 1&2&x\\ 3&{ - 1}&2 \end{array}} \right]\) and \(B = \left[ {\begin{array}{*{20}{c}} y\\ x\\ 1 \end{array}} \right]\)…
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