# Arithmetic : Exponents, Powers and Roots of Numbers

The power For example in 7 ^{4}, 4 is the exponent and 7 is the base.
The rules or laws of exponents are:
Here,
Consider the following examples:
Rule 1 : 2
If
This is obtained from the first law of exponents as follows: a = ^{n}a = ^{−n + n}a^{0} = 1, so a = 1/^{−n}a.^{n}For example, 2 ^{−4} = 1/2^{4} = 1/16 and (¼)^{−1} = 1/(¼) = 4
GMAT Math Review - Arithmetic : Practice Exercise for Powers & Roots of Numbers |

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