This applet can be used to determine whether a function is one-to-one or not, and also to restrict the domain to some interval where the function is one-to-one.[br][list][*]Enter a function of x in the input box.[br][/*][*]Drag the vertical slider up or down (or press the Play button) to find the intersecting points of the graph and the horizontal line.[br][/*][*]To see the x-coordinates of the intersection points, check the “show coordinates”.[br][/*][/list]If we want to define an inverse function then we have to find an interval where f(x) is one-to-one.[br][list][*]Drag the left and/or the right side of the blue segment under the graph to restrict the domain.[br][/*][/list]Use the second button on the toolbar to drag the viewing window, zoom in or zoom out if necessary.