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

• The equation x¹ = x (or a number raised to the 1 power is the number itself; this is also called the “rules of 1”).
• The equation x⁰ = 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 = 20¹.
• A negative exponent means to divide by that number of factors instead of multiplying. For example, 3^-3 is equal to 1/(3³). But there is a restriction to this rule: x^-n = 1/xⁿ only when x is not zero; if x is 0, then xⁿ is undefined.