MCQ
If matrix $A = \left[ {\begin{array}{*{20}{c}}
{\sin \theta }&{\cos ec\theta }&1\\
{\cos ec\theta }&1&{\sin \theta }\\
1&{\sin \theta }&{\cos ec\theta }
\end{array}} \right]$ is a non invertible matrix, then possible value of $'\theta'$ is
{\sin \theta }&{\cos ec\theta }&1\\
{\cos ec\theta }&1&{\sin \theta }\\
1&{\sin \theta }&{\cos ec\theta }
\end{array}} \right]$ is a non invertible matrix, then possible value of $'\theta'$ is
$($ where $n \in I)$
- A$n\pi + {( - 1)^n}\frac{\pi }{4}$
- B$n\pi + {( - 1)^n}\frac{\pi }{3}$
- C$n\pi + {( - 1)^n}\frac{\pi }{6}$
- ✓$2n\pi+\frac{\pi}{2}$