Zaid Berjis

Mathematics and physics you can see.

Interactive lessons, study guides and workbooks by Zaid Berjis. Every idea comes with a visualization you can change and explore.

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A square wave from sine waves

\(f_n(x) = \dfrac{4}{\pi} \displaystyle\sum_{k=1}^{n} \dfrac{\sin\big((2k-1)x\big)}{2k-1}\)
Sum of \(n\) terms Square wave

What you will find here

Three kinds of material, written for students who want to understand the idea, not only the answer.

  • Interactive lessons

    Complete lessons in mathematics and physics, each built around a visualization you can adjust. Free to use on this site.

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  • Study guides

    Nonfiction guides that explain one topic from the ground up, published as ebooks on Amazon Kindle.

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  • Workbooks

    Practice problems with worked solutions, plus study journals and planners for organizing revision.

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