Assignment 6.2: Investigation: Intervals of Increase/Decrease The graph of f(x) = x3 - 4x is given. The local maximum occurs at x ~ -1.2. The local minimum occurs at x #1.2 For question one, choose from the following: x 1.2 1. a) Over what values of x is f(x) increasing? b) Over what values of x is f(x) decreasing? 2. Determine the derivative of the function f(x) = x3 - 4x 3. Determine the x-intercepts of the derivative algebraically, to one decimal place. -54. What is the vertex of the derivative? 5. Use the x-intercepts and the vertex to graph the derivative. 6. Use the graph of the derivative to answer the following. (Consider using terms such as: negative, zero, positive) CONCLUSION: a) When f(x) is increasing, the derivative is b) When f(x) is decreasing, the derivative is c) When f(x) is at a local max/min, the derivative is