So I’ve been skipping my World of Warcraft time and reviewing calculus and differential equations so I don’t get too rusty. I almost immediately ran into an issue “reading” some of the set notation. It’s great because it’s compact and can communicate a lot of information but that doesn’t help if you can’t read it.

Take for example

{(x,f(x))|x∈A}

Doesn’t say much unless you can read it as “the set of all ordered pair x, f of x such that x is a member of set A”. Here are a few quick rules:

{ } denotes the set

( ) denotes and ordered pair

| “such that”

: also “such that” just in case things were too clear

∈ “is a member of”

∉ “is not a member of”

∪ union of two sets

∩ intersection of sets

So ℕ = {|*a*| : *a* ∈ ℤ} reads as “The set of natural numbers is equal to the absolute value of a such that a is a member of set ℤ”. Since ℤ is generally the set of ingeters { … ,-2, -1, 0, 1, 2, … } this means that ℕ = {0, 1, 2, … }

So now I can mostly read set notation again. Now I just need to learn MathML.