5. For each function, find the critical numbers. Use the first derivative test to identify the local maximum and minimum values. a. g(x) = 2x3 - 9x2 + 12x b. g(x) = x3 - 2x2 - 4x 6. Find a value of k that gives f(x) = x2 + kx + 2 a local minimum value of 1