If a+b =6 and ab =4 then what is the value of a3 + b3.

Option

A) 120

B) 125

C) 144

D) 81

Detailed solution

We know that a+b=6 and ab=4.

Using (a+b)² = a² + b² + 2ab

a² + b² = (a+b)² -2ab

a² + b² = 62 -2×4

a² + b² = 28

Using

(a³ + b³) = (a+b) (a² + b² – ab)

= ( 6 ) ( 28 – 4)

= 144

ANSWER 44