f(x)=-x^{3}-\frac{3}{2} x^{2}+6 x+6 (a) Find the stationary points of f, and give their exact - andy-coordinates. (b) Use the first derivative test to classify the stationary points that you found in part (a). (c) Sketch the graph of f, indicating the y-intercept and the points that you found in part (a). (You should draw this by hand, rather than using any software, and you can use different scales on the two axes if appropriate.) (d) Find the greatest and least values taken by f on the interval [-3, 3].

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