I'm stuck, what would be two inputs for this nonlinear equation?
f(x) = x³ - 7 x = -2 x = 2
The reason you have received no reply so far is because the way you typed your function is confusing.
You have 3 equal signs in the same line, is that what you wanted?
is your function f(x) = x3 ?
if you simply want f(-2) and f(2) that would be easy
f(-2) = (-2)^3 - 7(-2)
= 6
f(2) = 2^3 - 7(2)
= -6