Question:medium

If \[ A= \begin{bmatrix} \cos\alpha& 0 &\sin\alpha\\ 0& 1& 0 -\sin\alpha& 0 &\cos\alpha\\ \end{bmatrix} \] and \(A^2=A^T\) for one value of \(\alpha\in(0,\pi)\), then \(A^3=\):

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Whenever a matrix is orthogonal, replace \(A^T\) by \(A^{-1}\). This usually simplifies the problem immediately.
Updated On: Jun 18, 2026
  • \(I\)
  • \(A\)
  • \(3I\)
  • \(\begin{bmatrix}0& 0& 00& 3& 00& 0& 0\end{bmatrix}\)
Show Solution

The Correct Option is A

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