Question

if p, q and r are in continued proportion, prove that: p^2 + q^2 + r^2 = (p+q+r) (p-q+r)​

Answer 1

Answer:

as p.q.r are in proportion pr=q²

RHS=p²-pq+pr+pq-q²+rq+pr-qr+r²=p²+pr+q². as pr=q²

RHS=LHS=p²+q²+r²