Question

(P_q)^3+(q_r)^3_(r_q)^3

Answer 1

p^3 -q^3 -3p^2q +3pq^2 + q^3 -r^3 -3q^2r +3qr^2 -r^3 +q^3+3r^2q -3rq^2.

=p^3 + q^3 -2r^3-3p^2q + 3pq^2-6q^2r +6qr ^2