Answer:
a³ + b³
Explanation:
given the product
(a + b)(a² - ab + b²)
each term in the second factor is multiplied by each term in the first factor
a(a² - ab + b²) + b(a² - ab + b²) ← distribute parenthesis
= a³ - a²b + ab² + a²b - ab² + b³ ← collect like terms
= a³ + (- a²b + a²b) + (ab² - ab²) + b³
= a³ + b³