CUET · MATHS · PYQ PAPER 2025
If \(A=\left[\begin{array}{ccc}1 & 2 & 3 \\ -4 & -5 & -6\end{array}\right], \quad B=\left[\begin{array}{cc}2 & -3 \\ 4 & -5 \\ 2 & -1\end{array}\right]\) and \(B A=\left[b_{i j}\right]\), then \(\left(b_{23}-b_{31}\right)\) is equal to
- A 22
- B 36
- C 16
- D 27
Answer & Solution
Correct Answer
(B) 36
Step-by-step Solution
Detailed explanation
\(b_{23} = (4)(3) + (-5)(-6)\) \(b_{23} = 12 + 30 = 42\) \(b_{31} = (2)(1) + (-1)(-4)\) \(b_{31} = 2 + 4 = 6\) \(b_{23}-b_{31} = 42 - 6 = 36\)
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