Question 979706


{{{(q^3-p^3)/(pq^2 - qp^2)}}} = {{{((q-p)*(q^2 + qp + p^2))/(pq*(q-p))}}} = {{{(q^2 + qp + p^2)/(pq)}}} = {{{((q^2 - 2qp + p^2) + 2qp + qp)/(qp)}}} = {{{((q-p)^2 + 3qp)/(qp)}}} = {{{(q-p)^2/qp}}} + {{{(3qp)/qp)}}} >= {{{(3qp)/qp)}}} = {{{3}}}.


The proof is completed.