102 algebra De mystif ieD

DeMYSTiFieD / algebra DeMYSTiFieD / HuttenMuller / 000-0 / Chapter 5

Property 5 a

a

− (^1) =^1
This property says that a–1 is the reciprocal of a. In other words, a–1 means
“invert a.” or “take the reciprocal of a.”
EXAMPLES
2 1
2
− (^1) =
x
x
− (^1) =^1
x
y
x
y
y
x
y
xy x





 ==÷=⋅=
 1 − 1
11
2
3
3
2
^1




−
1
4
4
^1




 =
−
−



=−
3 −
10
10
3
1
Property 6 a
a
n
n
− =^1
Property 6 allows us to write an expression that has a negative exponent as an
expression without an negative exponent.
Property 6 is a combination of Properties 3 and 5:^111
a a
n aa
n n
= n



=()−−=.
EXAMPLES EXAMPLES