# Tag Info

### Does this geometry theorem have a name?

Even more is true for this theorem. Check out this drawing from Arseniy Akopyan wonderful book of Geometry in Figures (Second, extended edition, 2017). On page 65 we find Figure 4.7.29) In the ...
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### What is the name of the 65537-gon?

"$65537$-gon" is the name. Likewise "$257$-gon": writing (let alone saying) something like "diacosipentacontaheptagon" serves less to communicate $-$ if indeed it succeeds in communicating at all $-$...
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Accepted

### Tiling the plane with incongruent isosceles triangles

Q1: Yes. Any acute non-isosceles triangle can be tiled by three pairwise incongruent isosceles triangles, by connecting each vertex to the circumcenter. Start from some isosceles $T_0$ with repeated ...
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### Which theorems have Pythagoras' Theorem as a special case?

The Law of cosines is the first that comes to my mind: $$c^{2}=a^{2}+b^{2}-2ab\cos \gamma$$ (source: Wikipedia) If $\gamma$ is a right angle, its cosine is 0 and all that remains is Pythagoras' ...
Accepted

### Why is it so hard to prove Toeplitz' conjecture?

Let me elaborate on Sam Hopkins' comment. The main reason that makes this and other problems on continuous curves so hard is that a "simple closed curve" or "Jordan curve", i.e. a non-self-...
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### Which theorems have Pythagoras' Theorem as a special case?

Parseval identities in the theory of Fourier series and integrals.