Question

X+y=12, xy=27 find x^3+y^3

Answer 1

Given:-

x + y = 12

xy=27

To find:-

x³+y³

Solution:-

We know that,

(a+b)³=a³+b³+3ab(a+b)

Hence,

(x+y)³ = x³+y³+3xy(x+y)

Substituting the values of x+y and xy , we get

(12)³= x³+y³+3(27)(12)

1728 = x³+y³+972

→ x³+y³=1728-972

→ x³+y³=756

Hence, solved.