# Math

* [WolframAlpha](http://www.wolframalpha.com/)
* [ScienceWorld Physics](http://scienceworld.wolfram.com/physics/)
* [Videos lectures of Professor Gilbert Strang teaching linear algebra](http://ocw.mit.edu/courses/mathematics/18-06-linear-algebra-spring-2010/video-lectures/)
* [www.math.com](http://www.math.com/tables/)
* [Math Open Reference](http://www.mathopenref.com/)
* [The Incircle of a triangle](http://www.mathopenref.com/triangleincircle.html)
* [Incenter of a triangle](https://www.mathopenref.com/coordincenter.html)