Graph.tk is a free online graphing utility that I found in the Google Chrome Web Store. Graph.tk allows you to plot multiple functions through its dynamically resizing grid. To graph an equation on Graph.tk just click the “+” symbol to enter a new equation. Click here to watch a short video of Graph.tk in use. One thing that the video doesn’t show and isn’t clear the first time you use Graph.tk is that you need to delete the existing default equations before you start.

Applications for Education
Graph.tk probably won’t replace a TI-84 or similar graphing calculators, but it could be useful for doing some of the functions of those calculators. Like I mentioned in my post about the Web 2.0 Calculator, Graph.tk could be a resource for students who don’t have access to graphing calculators outside of their classrooms.