Correct Answer - Option 2 : 272
Given:
a + b = 6 , ab = 8
Concept:
a4 + b4 = [(a + b)2 – 2ab]2 – 2(ab)2
Calculation:
⇒ a4 + b4 = [(6)2 – 2 × (8)]2 – 2 × (8)2
⇒ a4 + b4 = [36 – 16]2 – 128
⇒ a4 + b4 = [20]2 – 128
⇒ a4 + b4 = 400 – 128 = 272
∴ The required result will be 272.
