Modify the function in Example 8.1 so that it becomes f (x) = x sin(x) for 0 ≤ x ≤ 30. (Here, sin(x) is the sine function from trigonometry. You can evaluate it with Excel’s SIN function.) Plot a lot of points from 0 to 30 to see what the graph of this function looks like. Then use GRG Nonlinear Solver to find its maximum. Try the following starting points (and don’t use the Multistart option): 1, 6, 15, 20, and 27. Report what you find. Then try Evolutionary Solver. Does it find the correct solution?