Enter the functions

Now you can enter the functions. Select three subitems of the item Change. A window should appear with a gadget. If there is already some text, delete it with right–Amiga–x. Then enter _a+_b. Press <RETURN>. The window disappears and appears right again. Enter the second function (that is 2*_a). After <RETURN>, you can enter the last function (that is _a(2*x), see ([*])). If you look at the subitem of Change, you should see your functions.