Question -
Answer -
Let’s take A tobe the first term and R to be the common ratio of the G.P.
Then according to thequestion, we have
ARp–1 = a
ARq–1 = b
ARr–1 = c
Then,
aq–r br–p cp–q
= Aq–r × R(p–1)(q–r) × Ar–p × R(q–1)(r–p) × Ap–q × R(r –1)(p–q)
= Aq – r + r – p + p – q × R (pr – pr – q + r)+ (rq – r + p – pq) +(pr – p – qr + q)
= A0 × R0
= 1
Hence proved.