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CUET · MATHS · PYQ PAPER 2025

If \(A=\left[\begin{array}{cc}1 & 5 \\ 7 & 12\end{array}\right], B=\left[\begin{array}{ll}9 & 1 \\ 7 & 8\end{array}\right]\) and \(C\) are three matrices such that \(3 A+5 B+2 C=0\), then the matrix \(C\) is equal to

  1. A \(\left[\begin{array}{ll}-48 & -20 \\ -56 & -76\end{array}\right]\)
  2. B \(\left[\begin{array}{ll}-24 & -10 \\ -28 & -38\end{array}\right]\)
  3. C \(\left[\begin{array}{cc}-48 & 20 \\ 56 & -76\end{array}\right]\)
  4. D \(\left[\begin{array}{ll}24 & 10 \\ 28 & 38\end{array}\right]\)
Verified Solution

Answer & Solution

Correct Answer

(B) \(\left[\begin{array}{ll}-24 & -10 \\ -28 & -38\end{array}\right]\)

Step-by-step Solution

Detailed explanation

\(2C = -3A - 5B\) \(C = \frac{1}{2}\left(-3\left[\begin{array}{cc}1 & 5 \\ 7 & 12\end{array}\right] - 5\left[\begin{array}{ll}9 & 1 \\ 7 & 8\end{array}\right]\right)\)…