If ai ε R, i = 1, 2, 3, .......n and all ai’s are distinct such that
\(\left(\sum\limits_{i =1}^{n-1}{a_i}^2\right)x^2 + 2\left(\sum\limits_{i =1}^{n-1}{a_i}a_{i+1}\right)x+ \sum\limits_{i=2}^n {a_i}^2 \le 0\), then a1, a2, ......... are in
a. G.P
b. A.P
c. H.P
d. none of these
