In our definition of an exponential function, we ruled out negative values of a. The author of

Question:

In our definition of an exponential function, we ruled out negative values of a. The author of a textbook on mathematical economics, however, obtained a “graph” of y = (-2)^x by plotting the following points and drawing a smooth curve through them.The graph oscillates very neatly from positive to negative values of y. Comment on this approach. (This exercise shows the dangers of point plotting when drawing graphs.)