Question

Let A and B denote the statements
A : cos α + cos β + cos γ = 0
B : sin α + sin β + sin γ = 0
If cos (β – γ) + cos (γ – α) + cos (α – β) = $-\frac{3}{2}$, then :
(a) A is false and B is true
(b) both A and B are true
(c) both A and B are false
(d) A is true and B is false

Answer 1

c . both A and B are false