Last Saturday, I was presenting at a conference and a participant asked if FX Graph/FX Draw could restrict the domain of a function BUT show the end points as arrows. In other words, could it show this

instead of this.

The participant knew how to restrict domains using bracket notation but was getting output such as this

At the time, the answer was “No” but I could see her point. The first graph is much better at showing that a standard graph has been moved around the plane. Drawing the full curve over the plane makes the magenta parabola look bigger than the red one (even thought they are the same) simply because more of the curve has been drawn.

So We Fixed It!
The good news is that today, just four days later, we have added the feature to FX Graph 6 and FX Draw 6! We are ALWAYS happy to listen to ideas!

To use the new feature, you write a bracket domain but use braces to indicate that an arrowhead should be used instead of an open or closed circle. In other words, type something like

x2 {-2,2}

You can also mix and match, having arrowheads on one end and an open or closed circle on the other. eg x2 [-2,4}

Note that this new feature will only be available on the new FX Draw 6 and FX Graph 6.