Multiplying and Dividing Rational Expressions
Multiplying rational expressions
o We can work this out by hand. Multiply straight across o
We could also reduce the fractions first could we not. In most
cases it is easier to remove the common factors before one begins
o With these type of questions, you must state any restriction
on the denominator before you begin to cancel
o Factor each polynomial expression to lowest terms. Then
cancel like terms.
o Because it is multiplication, we can cancel out like terms
from top and bottom.
ONLY TERMS WHICH ARE MULTIPLIED CAN BE REDUCED.
Division of rational Expressions
o The rule is to invert and multiply the 213 nd fraction. Then
we follow our simply rules for multiplication.
o However it is often easier to reduce the fraction before
hand, then multiply.
o State restrictions of the 1st denominator and 2 nd numerator
(factor as needed)
o Factor all expressions, invert 213 nd fraction, cancel all