Matt Enlow

Matt Enlow

@unsolvedmre.bsky.social

Mathematician, math teacher, math enthusiast, math/art-ist. Universal humanizer.

1.5K followers715 following877 posts

It doesn't make intuitive sense to me that local mins/maxes can't occur at endpoints of the domain. The function f(x)=x² restricted to [-1,2] ought to have local maxima @ x=-1 and x=2. How "flexible" is this def'n? How much harm would I be doing my students if I included endpoints as local extrema?

Write a single equation in x and y, using only the 4 arithmetic operations and the absolute value function (finitely many times), whose graph is this square. #iTeachMath #math #maths #MathSky

Suppose a hollow cone with radius 15cm and height 20cm is being filled with water. If it were base-down, the area of the surface of the water would decrease as the cone filled; if, instead, it were balancing on its point, the area of the surface of the water would increase as the cone filled. [1/2]

But THIS cone is lying on its side (so that it's tangent to the ground at a slant-height segment). So the area of the water surface will initially increase, but then decrease, until the cone is full. What would the height of the water be when the area of the water's surface is at its greatest?

The integers from 1 to 18 can be arranged in a circle so that, when following the circle (counter-clockwise in the below example), every number is the sum of the previous two (mod 19). For what other mods can we do this? That is, for what other integers m can the integers 1 to m-1 be so arranged?

Currently wondering: Can an equilateral pentagon have five distinct interior angle measures that are all rational multiples of π radians? If we remove "distinct," there's at least the regular pentagon with five angles of 3π/5, and another pentagon with two π/2's, two 5π/6's, and a π/3. #MathSky

I always roll my eyes when an A.I. chatbot describes something as "fun," or reports being "curious" about something. Because... no. That's not what's happening. This was a new one on me, though. Why not just omit the "us"?

A parabola rolls along a flat surface. What path does its focus (the red point) trace? Another parabola? Or something else? #iTeachMath #math #maths #mathgif #mathgifs #mathsgif #mathsgifs

Today in Advanced Topics we tried to create a "quadratic formula" for solving quadratic equations in ℤₙ. I'd never done that before. Wasn't planning on doing it today. But that's where our rabbit hole led us. We haven't worked out all the kinks, but the messiness is part of the fun. (Ask any kid.)

An xy projection of the 3D Halverson attractor. I coded it in #Mathematica, then asked #ChatGPT to port it to html/js so it can run in a browser. That's what you're seeing here.

My 15yo son manages to get pizza sauce on every new article of clothing the first time he wears it. Even if we haven't eaten pizza. Somehow he still makes it happen.

One minute you're puzzling over a simple probability question, the next minute you're unironically typing out an expression that looks like this

Matt Enlow@unsolvedmre.bsky.social

Okay this one is a beast #math #mathchat #maths #mathschat #probability #iTeachMath #MathSky