[latexpage]

## Sets and Types of Numbers

**Prime numbers**= postive integer that are only divisible by themselves and 1- The lowest prime number is 2 (this is also the only even prime number)
- Note: by convention, 1 is NOT considered a prime number
- Cannot be factorized ⇒ prime numbers are considered the fundamental building blocks of positive integers
- Important concept for coding

- The Riemann hypothesis involves the distribution of prime numbers among the positive integers

**Composite numbers**= positive integers that are neither 1 nor a prime- Every composite number can be written as a unique product of prime factors
- Examples:

- Examples:
- Currently, there is no genral algorithm that can determine the uniqe combination of prime factors for any given positive integer
- This process is an ideal basis fo encryption systems

- Every composite number can be written as a unique product of prime factors

## Trigonometry

### Tangent Identities

### Pythagorean Identities

### Periodic Identities

## Sources:

- Glendinning, P. (2013).
*Math in minutes*. New York, NY: Quercus.