There are several simple rules when it comes to exponents. These include the following:

- The equation
*x*^{1} = *x* (or a number raised to the 1 power is the number itself; this is also called the “rules of 1”).
- The equation
*x*^{0} = 1 (unless *x* = 0, then this is referred to as undefined; this is also called the “zero rule”).
- A number without an exponent has an exponent of 1, as in 20 = 20
^{1}.
- A negative exponent means to divide by that number of factors instead of multiplying. For example, 3
^{-3} is equal to 1/(3^{3}). But there is a restriction to this rule: *x*^{-n} = 1/*x*^{n} only when *x* is not zero; if *x* is 0, then *x*^{n} is undefined.