Question

If a+ b = 6 and ab = 2 find a^3 + b^3

Answer 1

Answer: 180

Step-by-step explanation:

This is just testing if you know the sum of cubes formula:

$a^3 + b^3 = (a+b)(a^2 - ab + b^2) = (a+b)((a+b)^2 - 3ab)$

Plugging in the respective values, you get

$a^3 + b^3 = (6)(6^2 - 3(2)) = \boxed{180}$