​If A = [(cosα -sinα) (sinα cosα)] and A + A' = I2 , then α =

Question

If \(A=\left[\begin{array}{cc}\cos \alpha & -\sin \alpha \\ \sin \alpha & \cos \alpha\end{array}\right]\) and \(A+A^{\prime}=I_{2},\) then \(\alpha=\)

(A) \(\pi\)

(B) \(\frac{\pi}{3}\)

(C) \(\frac{3 \pi}{2}\)

(D) \(\frac{\pi}{6}\)

Answer 1

सही विकल्प है (B) \(\frac{\pi}{3}\)