Question

Pls help me with this question

Answer 1

Answer:

Given that, a + b = 1

Taking cube of both sides, we get

(a + b)3 = 1

⇒ a3 + b3 + 3ab(a + b) = 1

⇒ a3 + b3 + 3ab = 1

Short Trick:

Here, One equation and two variable, so a and b can have infinite value.

let suppose that b = 0

⇒ a = 1

So, a3 + b3 + 3ab

⇒ 13 + 0 + 0 = 1