(x+1)(x^2-x+7) = x^3 - x^2 + 7x + x^2 - x + 7= x^3 + 6x + 7
(a+b)(a^2-3ab+b^2) = a^3 - 3a^2b + ab^2 + ba^2 - 3ab^2 + b^3= a^3 - 2a^2b - 2ab^2 + b^3
(p-q)(p^2+3pq+q^2) = p^3 + 3p^2q + pq^2 - p^2q - 3pq^2 - q^3= p^3 - q^3
(x+1)(x^2-x+7) = x^3 - x^2 + 7x + x^2 - x + 7
= x^3 + 6x + 7
(a+b)(a^2-3ab+b^2) = a^3 - 3a^2b + ab^2 + ba^2 - 3ab^2 + b^3
= a^3 - 2a^2b - 2ab^2 + b^3
(p-q)(p^2+3pq+q^2) = p^3 + 3p^2q + pq^2 - p^2q - 3pq^2 - q^3
= p^3 - q^3