CHAPTER 8 REVIEW
PROCEDURES FOR RATIONAL EXPRESSIONS (Fractions)
SIMPLE FRACTIONS
Reducing simple fractions- one polynomial in the numerator and one
in the denominator
*Factor the numerator ( top of the fraction)
*Factor the denominator (bottom of the fraction)
*Reduce common terms in the numerator and denominator (using the identity
property)
MULTIPLYING/DIVIDING FRACTIONS
Multiplying fractions, you multiply across the top and across the
bottom and reduce common terms as in simple fractions above
Dividing fractions you multiply the numerator by the reciprocal
of the denominator
(Flip the bottom fraction and use the flipped term to multiply the
top fraction)
ADDITION AND SUBTRACTION OF FRACTIONS
*Find the LCD- Least Common Denominator from all the fractions being added/subtracted
*Make each fraction have the same denominator by using the identity
property to multiply the top and bottom of each
fraction by the missing part of the LCD
*Combine and simplify the numerators of all the fractions
*Place the combined and simplified numerator over the denominator
*Simplify if possible using the procedures from simple fractions provided
above (factor the
numerator
and denominator and reduce like terms)
NOTE: The denominator does not go away!!!!!!
COMPLEX FRACTIONS
Method #1
*Create a fraction in the numerator using the addition rules provided
above
*Create a fraction in the denominator using the addition rules provided
above
*Invert the denominator and use this fraction to multiply the numerator
as described above
*Reduce common terms using the identity property as you did in simple
fractions above
Method #2
*Find the LCD of all the fractions in the top and bottom of the complex
fraction
*Multiple every fraction in the top and bottom by the LCD and reduce
each fraction
*Simplify and reduce the denominator and numerator if possible
SOLVING EQUATIONS WHICH CONTAIN FRACTIONS
*Find the LCD of all the fractions in the equation, both right side and
left side of the equal sign
*Multiply each and every term on both sides of the equal sign by the
LCD
*Reduce the fractions – (The denominators do go away)
*Solve the remaining equation
*Check your answer by substituting the result back into the original
equation
*Take special care to make sure no denominator in any fraction becomes
zero. If any
denominator
does become zero then the result is not acceptable and the answer becomes
no solution or null set.