If a + b = 10 and ab = 6, then the value of a3 + b3 is:
Show answer & explanation
Correct answer: B
Explanation
The correct answer is Option 2 i.e. 820.
We know that,
(a + b)3 = a3 + b3 + 3ab(a + b)
On putting the given values
⇒ 103 = a3 + b3 + 3 × 6(10)
⇒ 1000 = a3 + b3 + 180
⇒ a3 + b3 = 1000 - 180
⇒ a3 + b3 = 820