COMEDK · Maths · 21. Matrices
If matrix \(A=\left[\begin{array}{cc}2 & -2 \\ -2 & 2\end{array}\right]\) and \(A^{2}=p A\), then the value of \(p\) is
- A 6
- B \(-4\)
- C 4
- D 8
Answer & Solution
Correct Answer
(C) 4
Step-by-step Solution
Detailed explanation
Given \(A = \begin{bmatrix} 2 & -2 \\ -2 & 2 \end{bmatrix}\). Calculate \(A^{2}\) by multiplying \(A\) with itself: \(A^{2} = \begin{bmatrix} 2 & -2 \\ -2 & 2 \end{bmatrix} \begin{bmatrix} 2 & -2 \\ -2 & 2 \end{bmatrix}\)…
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