If you know how to multiply 2×2 matrices, and know about complex numbers, then you’ll enjoy this connection. Any complex number...

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## Products of Sums of Two Squares

Here’s a nice theorem due to Fibonacci, in 1202. Theorem. If integers N and M can each be written as the...

Continue reading...## Chords of a Unit Circle

Take N equidistant points on the unit circle. Pick one of those points, then draw chords from it to all...

Continue reading...## Complex Roots Made Visible

Everyone learns that the roots of a polynomial have a graphical interpretation: they’re the places where the function crosses the x-axis. But...

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