The next two Monkey Rules have to do with the derivatives of specific functions. First we start with the exponential function e[sup]x [/sup]which is plotted below. As usual, a point A has been plotted on the graph, and the tangent line, g, to the function at A has been created. Use your usual code[br][br][code](x(A),slope(g))[br][br][/code][br]to track the slope of the tangent line as A moves, and get a look at the graph of the derivative of e[sup]x[/sup].

If you're a tad confused, that's normal. It is true that the point B you created is exactly equal to point A. But what does that mean? Well, if you stop and think, it can only mean one thing: that the derivative of e[sup]x[/sup] is itself! And that's our next monkey rule:[br][br][b]Monkey Rule 4[/b]: The derivative of e[sup]x[/sup] is e[sup]x[/sup] (itself!).