Question

If x+y=1 then x cube - y cube + 3xy = ?

Answer 1

Answer:

X+y = 1

(x+y)³ = (1)³

x³ + y³ + 3xy(x+y) = 1

x³ + y³ + 3xy(1) = 1

x³ + y³ + 3xy = 1

(a+b)³ = a³ + b³ +3ab(a+b)