Question

The graph of f(x) = x3 − 7x − 6 is shown.



Based on the graph, what are all of the solutions to f(x) = x3 − 7x − 6?

x = −6
x = −2, −1
x = −2, −1, 3
x = −6, −2, −1, 3

Answer 1

f(x)=0 when x is a real root. Factor:
x^3−7x−6 = (x+1)(x+2)(x−3),
so the solutions are x = −2, −1, 3.