| I think you need to know only a few formulas, but lots of facts (admittedly, these two words overlap a bit).
Most of the needed formulas are given, although there are some others, perhaps too "obvious" for many people here, such as: x^-n = 1/x^n ("^" means "to the power of"), average=sum/N, the difference of squares a^2-b^2=(a+b)(a-b), the distance formula (though this just comes from the pythagorean theorem), and so on.
By "facts" I mean things like: two lines intersecting make two angles that add to 180 degrees, an equilateral triangle has three angles of 60 degrees, the slope of a line is rise/run, etc. etc.
I've collected a pile of these facts along with the few formulas into short pdf files (free and non-commercial) on my web site; if people are interested, I'll post the link... |