Pre-Algebra Demystified

(Marvins-Underground-K-12) #1

Exponents


When the same number is multiplied by itself, the indicated product can be
written inexponential notation. For example, 33 can be written as 3^2 ; there
the 3 is called thebaseand the 2 is called theexponent. Also,


3  3  3 ¼ 33
3  3  3  3 ¼ 34
3  3  3  3  3 ¼ 35 ;etc.
32 is read as ‘‘three squared’’ or ‘‘three to the second power,’’ 3^3 is read as
‘‘three cubed’’ or ‘‘three to the third power,’’ 3^4 is read as ‘‘three to the fourth
power,’’ etc.


Math Note: When no exponent is written with a number, it is
assumed to be one. For example, 3¼ 31.

EXAMPLE

Find 5^3.


SOLUTION

53 ¼ 5  5  5 ¼ 125

EXAMPLE

Find 2^8.


SOLUTION

28 ¼ 2  2  2  2  2  2  2  2 ¼ 256

Exponents can be used with negative numbers as well. For example,ð 8 Þ^3
meansð 8 Þð 8 Þð 8 Þ. Notice that in the case of negative numbers, the
integer must be enclosed in parentheses. When thesign isnotenclosed in
parentheses, it isnotraised to the power. For example, 83 means 8  8 8.


EXAMPLE

Findð 5 Þ^4.


CHAPTER 2 Integers 31

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