If (a + b) = 3 and ab = 2, then (a 3 + b 3 ) = ?

If (a + b) = 3 and ab = 2, then (a ³ + b ³ ) = ?

A 6

B 7

C 8

D 9

Solution

Correct Answer: Option D

দেওয়া আছে, a + b = 3

ab = 2

∴ a ³ + b ³ = (a+b) ³ - 3ab(a+b)
= 3 ³ - 3. 2. 3
=27-18 = 9