જો $b$ અને $c$ અસમરેખ સદિશો હોય, $|c| \neq 0$, $a \times(b \times c)+(a \cdot b) b=(4-2 \beta-\sin \alpha) b+\left(\beta^2-1\right) c$ અને $(c \cdot c) a=c$ હોય, તો અદિશો $\alpha$ અને $\beta$ શું થાય?

• A
  $\alpha=\frac{\pi}{2}+2n\pi, n \in Z ; \beta=1$
• B
  $\alpha=\frac{\pi}{2}+n\pi, n \in Z ; \beta=1$
• C
  $\alpha=\frac{\pi}{2}+(2n+1)\frac{\pi}{2}, n \in Z, \beta=2$
• D
  $\alpha=(2n+1)\frac{\pi}{2}, n \in Z, \beta=\frac{3}{2}$