Negative Exponents

Definitions

Exponents are also called Powers or Indices

The exponent of a number says how many times to use the number in a multiplication.

Example

72 = 7 × 7 = 49

72 can be called 7 to the second power or 7 to the power 2 or simply 7 squared

General form of exponent

an tells you to use a in a multiplication n times

Exponent

Those are positive exponents

How About Negative Exponents?

Dividing is the inverse (opposite) of Multiplying.

A negative exponent means how many times to divide by the number.

Example

2-1 = 1 ÷ 2 = 1/2 = 0.5

many divides

2-2 = 1 ÷ 2 ÷ 2 = 0.25

Or

2-2 = 1 ÷ (2 × 2) = 1/22 = 1/4 = 0.25

a-n tells you to divide by a n times

Negative Exponent

Easy Way

An easier way to handle negative exponents:

1. Calculate the positive exponent an

2. Then take the Reciprocal 1/ an

Learn More

Exponents

Fractional Exponents

Simplifying Square Roots

Cube Numbers and Cube Roots

Algebra Index