Question

Approximate the real number solution(s) to the polynomial function f(x) = x3 − 4x2 + x + 6.

Answer 1

C is the correct answer because that's the only answer where all the numbers (i.e. 3, -1, 2) all, when plugged into the function, equal 0. For example:

3³ - (4 × 3²) + 3 + 6 = 0
-1³ - (4 × (-1)²) + (-1) + 6 = 0
2³ - (4 × 2²) + 2 + 6 = 0

As we see, everything adds up to 0. So, C is the correct answer.