Score: 2/12
2/12 answered
Given the function g(x) = 4x^(3) + 42x^(2) + 120x, find the first derivative, g'(x).
g'(x) =
Notice that g'(x) = 0 when x = -2, that is, g'(-2) = 0.
Now, we want to know whether there is a local minimum or local maximum at x = -2, use the second derivative test.
Find the second derivative, g''(x).
g''(x) =
Based on the concavity of g(x) at x = -2, does this mean that there is a local minimum?