Rational Expressions 145Step 2. Divide out common numerator and denominator factors.=
()()
− ()()
⋅
()()+ ()()
()()+ ()()
(^2) ( ++
1 ( −−
)( −−
)( ++
++ ))((
++ ))((
Step 3. Multiply the remaining numerator factors to get the numerator of
the answer, and multiply the remaining denominator factors to get
the denominator of the answer.=
−=−
2
1
2
Step 4. Review the main results.24
39
56
2
1
2
2
2x
xx
− xx 5⋅
−
+ 55
=
()()xx 22
− 1 ()()xx 33⋅
()()xx+ 333 ()()xx 33
()()xx+ 222 ()()xx 33=−
Dividing Algebraic Fractions
To divide algebraic fractions, multiply the fi rst algebraic fraction by the
reciprocal of the second algebraic fraction (the divisor).Problem Find the quotient:xx
xxxx
x2
22
221 x
632 x
− 4÷
3 x
−.
Solution
Step 1. Change the problem to multiplication by the reciprocal of the
divisor.xx
xxxx
x2
22
221 x
632 x
− 4÷
3 x
−=
−
⋅
xx −
xxx
xx−2
22
221 x+
64
32 x+Step 2. Factor all numerators and denominators completely.