Added introduction

src/Advanced/Fast Inverse Root/parts/00 intro.typ

@@ -36,10 +36,10 @@ This code defines a function `Q_sqrt`, which was used as a fast approximation of
 
 #v(3mm)
 
-The key word here is "fast": _Quake_ ran on very limited hardware, and traditional approximation techinques (like Taylor series)#footnote[In fact, Taylor series aren't used today, and for the same reason: there are better ways.] were too computationally expensive to be viable.
+The key word here is "fast": _Quake_ ran on very limited hardware, and traditional approximation techniques (like Taylor series)#footnote[In fact, Taylor series aren't used today, and for the same reason: there are better ways.] were too computationally expensive to be viable.
 
 #v(3mm)
 
 Our goal today is to understand how `Q_sqrt` works. \
 To do that, we'll first need to understand how computers represent numbers. \
-We'll start with simple binary---turn the page.
+We'll start with simple binary integers---turn the page.