Let A and B denote the statements A : cos a + cos b + cos g = 0 B : sin a + sin b + sin g = 0 If cos (b – g) + cos (g – a) + cos (a – b) = 3 2 – , then :[

Let $\mathbf{A}$ and $\mathbf{B}$ denote the statements

$\mathbf{A}: \cos \alpha+\cos \beta+\cos \gamma=0$

$\mathbf{B}: \sin \alpha+\sin \beta+\sin \gamma=0$

If $\cos (\beta-\gamma)+\cos (\gamma-\alpha)+\cos (\alpha-\beta)=-\frac{3}{2}$, then :