x+y = 4, xy = 5 হলে, (x³+y³)² এর মান কত?

x+y = 4, xy = 5 হলে, (x³+y³)² এর মান কত?

A 16

B 4

C 8

D 10

Solution

Correct Answer: Option A

x³+y³ = (x+y)^3 - 3xy(x+y)

= (4)^3 - 3×5×4 = 64 - 60 = 4

(x³+y³)² = (4)² = 16