In anticipation of ever being stuck on a deserted island, and wanting to have a minimum of math formulas to remember (from which other formulas can be derived), what would they be? Let’s say that you expect to spend a few years on the island before getting rescued, and your job when you get home depends on math, and you don’t want your math knowledge to get rusty. Here are a couple candidates for useful formulas.

*Trigonometric Formulas*

The following equation can be used to find many trig identities, and also to derive what many mathematicians consider to be the most beautiful formula in math. Read more…Desert_Island_Formulas