When you multiply a factor by itself, you can write a numerical expression using exponents.   The number 2³ is written in exponential form, where 2 is the base and 3 is the exponent.

An exponent, or power, tells how many times the base is used as a factor.

2x³   

The 2 is the coefficient. X is the variable. 3 is the exponent.

 

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