If `a , b ,a n dc` are respectively, the pth, qth , and rth terms of a G.P., show that `(q-r)loga+(r-p)logb+(p-q)logc=0.`

If a,b,c are respectively the p^(th),q^(th) and r^(th) terms of a G.P.show that (q-r)log a+(r-p)log b+(p-q)log c=0

(iii) If a,bc are respectively the pth,qth and rth terms of the given G.P. then show that (q-r)log a+(r-p)log b+(p-q)log c=0, where a,b,c>0.

If a, b, c be the pth, qth and rth terms of a G.P., then (q-r) log a+ (r- p)log b+ (p-q) log c is equal to (A) 0 (B) abc (C) ap+bq+cr (D) none of these

Suppose a, b, c gt 0 and are respectively the pth, qth and rth terms of a G.P. Let x=(loga)i+(logb)j+(logc)k y=(q-r)i+(r-p)j+(p-q)k If angle between x and y is kpi , then k = ______