A side note on the grapher: you can sum any function you want, not just sine and cosine.

]]>That looks great!. All worked ok. And I had a 'play' with the grapher. Years ago a neighbour asked me to help with his maths course. He was struggling with fourier and his notes were confused and had bits missing. I'd never done any fourier so we learnt it together. I made graphs using BBC Basic on my Archimedes computer (oh happy days!). Your notes make it clear why it works and the grapher does in seconds what it took us hours to construct.

Many thanks!

Bob

]]>I'm not as *au fait* with Fourier series (and analysis topics in general) as I am with other, more algebraic areas of mathematics, so it's great to learn something new.

Please let me know what you think, and if there are any errors at all.

]]>