Answer:
a³+b³
Step-by-step explanation:
this is formula. You can also refer to the attachment
(a + b) (a² - ab + b) = a*(a² - ab + b) + b(a² - ab + b)
= a*a² - a*ab +a*b + b*a² - b*ab + b*b
= a³ - a²b + ab + a²b -ab² + b²
= a³ - a²b + a²b + ab - a²b + b²
= a³ + ab - a²b + b²
