# 5. Graphs Using a Computer Algebra System

The graph of

*z*= 4

*x*

^{3}+

*y*

^{3}

Almost all your mathematics subjects require you to draw graphs, and you can get more insights into what's going on from such graphs. It's an important skill to be able to sketch curves on paper, but sometimes we have no idea what a function is supposed to look like.

We now have many tools which can help us to do mathematics, and especially draw graphs.

Once you start using a Computer Algebra System you'll find that it changes your whole view on mathematics. It takes a lot of the tedium out of algebra and frees up time to think about what you are doing.

## Commercial computer algebra systems

Some of the many commercial CASs available:

- Matlab - an industry leader (and expensive)
- MathCad - a sophisticated CAS (also expensive)
- Mathematica - also very sophisticated and also has a Web output. The best way to access Mathematica (for free) is via Wolfram|Alpha.
- Scientific Notebook (used in Interactive Mathematics. See SNB Information) and the related product Scientific Workplace

## Open Source Computer Algebra Systems

For those of you on a tight budget (aren't we all?), here's a few open source computer algebra systems. Many of them require some programming expertise.

## Free online graphers

These are all quite easy to use, and don't require programming.

- Desmos
- JSXGraph (on IntMath)
- Graphs using SVG (on IntMath)
- 3D grapher (on IntMath)
- GraphSketch
- Here's a review of 2 free math graphing software packages

## Graphics Calculators

Graphics calculators have become quite sophisticated, but usually have small screens with poor resolution, making it difficult to see details in the graph. However, they are certainly better than nothing!