## Proof: The rationality of the y-intercept

Theorem: Given a quadratic function with rational roots, the \(y\)-intercept is rational if and only if the stretch is rational. Proof: If \(f\) is a quadratic ...

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# Category: Other mathematics

## Proof: The rationality of the y-intercept

## Logarithms: The Dark Sorcery

## The Problem with Mathematical Notation

## Adding vs. Multiplying

## The Math Meme That Would Not Die

## Deriving Euler’s Identity

## The Natural Base e: Thoughts on Teaching

## The Problem with Problems

## Some Thoughts on Teaching Mathematics

## Dividing and remainders

Theorem: Given a quadratic function with rational roots, the \(y\)-intercept is rational if and only if the stretch is rational. Proof: If \(f\) is a quadratic ...

I used to hate logarithms. They were hopelessly confusing. Sort of like this: https://www.smbc-comics.com/comic/operations This is the third year now that IR...

Mathematics is beautiful. Mathematical notation, meanwhile, is a horrid mess second only to English itself for its arbitrariness. For instance, basic arithmetic...

We tend to act as if multiplying is repeated addition. This misses a key, crucial difference between the two operations: WE CANNOT ADD UNLIKE THINGS. We can abs...

Some version of this question keeps getting asked on the internet. What is \(8\div2(2+2)\)? Some background The strength of mathematical notation is at the inte...

Euler’s Identity has been called “the most beautiful equation” in mathematics. It neatly encapsulates five key values and three operators into...

In “Burn Math Class”, Jason Wilkes spends quite a few pages deriving the value of \(e\). I did not notice him at any point mentioning compound inter...

I’m currently reading “Burn Math Class,” and it’s got me thinking about language. Yesterday, I saw an item about teaching students why c...

This morning, I was reading the NCTM blog, and the subject was on students struggling with systems of linear inequalities. First, as background: I don’t h...

As a high school teacher, I struggle routinely with getting students to understand that \(x/0\) is undefined. Students don’t seem to understand that divis...