Negative Exponents:

The rules for positive exponents apply to negative exponents.  a^-n is described as follows:

a^-n = a^-n = 1/aⁿ

aⁿ = 1/a^-n

For example a⁵/a² =a^5.2 as shown earlier. If 1/a² is written as a^-2 and the rules for multiplication are applied to this a⁵ × a^-2 = a^5-2 = a³. Thus writing 1/aⁿ as a -n and applying the rules for multiplication yields the same results as 1/aⁿ and applying the rules of division.

Examples:

c^-2 = 1/c²

x³ = 1/x^-3