Question

.If x + y = 9 and xy = 23, find the value of (x

3 + y3

).​

Answer 1

Answer:

108

Step-by-step explanation:

Given,

x+y = 9 and xy = 23

⇒ (x+y)² = 9² = 81

⇒x²+y²+2xy = 81

⇒x²+y²+2×23 = 81

⇒x²+y² = 81 -46 = 35

∴ ,  x³ + y³ = (x+y)(x²+y²-xy) = 9(35-23) = 9×12 = 108