math.GM

This is an arXiv category tag for "general mathematics".

When does a polynomial with real coefficients have only real roots? Here's one way to determine it.
Last updated on 4 min read expository

Driving down the highway in upstate Michigan yesterday, I saw a State Police billboard that states (I paraphrase) Drivers who text are …
Last updated on 7 min read expository

Here's a slightly non-obvious relation between some angles, that I ran into accidentally. Claim: (angles below given in degrees) \[ …
Last updated on 1 min read mathematical diversions

A short note about an implicit assumption behind the notion of expectation values, and how it relates to economics applications.
Last updated on 7 min read mathematical diversions

The Kempner series recently regained some notoriety due to a Saturday Morning Breakfast Cereal comic (the last panel). The observation …
Last updated on 3 min read expository

We describe a theorem due to Mihai Mariş concerning the symmetries of ground states.
Last updated on 13 min read expository

When does the decimal expansion of a number end with one digit repeated?
Last updated on 3 min read mathematical diversions

We give a proof of the irrationality of π.
Last updated on 5 min read expository