defence exam Agniveer Vayu Group X & XY Mock Test 01/2026 Mathematics Matrices Operations on Matrices
If \({A_\alpha }\, = \,\left[ {\begin{array}{*{20}{c}} {\cos \alpha }&{\sin \alpha } \\ { - \sin \alpha }&{\cos \alpha } \end{array}} \right] \), then determinant of \({A_{\pi /5}}{A_{\pi /4}}{A_{3\pi /10}}\) =
1
\(\sqrt 2 \)
2
\(1 \over \sqrt 2 \)
3
0
4
1