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${\text{a}}^{\text{x}}→$a is the base and x is exponent.

The power is the result of repeated multiplication of the same factor.

The expressionsa^xthis means that a has been used as a factor x times

Example: Find the base and the power of 2⁷

Rule: ${\text{a}}^{\text{x}}→$a is called base and x is power.

a = 2 and x = 7

Base = 2 and power = 7

To express the power in words, write:2raised to the power 7.

In repeated multiplication: $2 · 2 · 2  · 2 · 2 · 2 · 2 $

Evaluate: $2^7=2 · 2 · 2  · 2 · 2 · 2 · 2 =128$

Write the power in words and as a repeated multiplication. Then evaluate the power$5^4$

According to the exponent rule:

${\text{a}}^{\text{x}}→$a is called base and x is power.

a = 5 and x = 4

To express the power in words, write: 5 raised to the power 4.

In repeated multiplication:$5^4$$=  5 · 5 · 5 · 5$

Evaluate: $5^4  =  5 · 5 · 5 · 5 =  625$