GMAT Quantitative Review
3.0 Math Review
3.2 Algebra
7. Exponents
A positive integer exponent of a number or a variable indicates a product, and the positive integer is the number of times that the number or variable is a factor in the product. For example, x5 means (x)(x)(x)(x)(x); that is, x is a factor in the product 5 times.
Some rules about exponents follow.
Let x and y be any positive numbers, and let r and s be any positive integers.
1. (1) ; for example, .
2. (2) ; for example, .
3. (3) ; for example, .
4. (4) ; for example, .
5. (5) ; for example, .
6. (6) ; for example, .
7. (7) ; for example, .
8. (8) ; for example, and .
It can be shown that rules 1–6 also apply when r and s are not integers and are not positive, that is, when r and s are any real numbers.