Chapter 7:Rational Algebraic

FunctionsSection 7-8:

Sums and Differences of Rational Expressions

ObjectivesBe able to add or subtract several rational expressions and simplify the result.

Example:

Find the LCM!!!!!

2 2

7 1 6

2 3 2

x x

x x x x

Ideas to keep in mind when adding/subtracting rational expressions:

If any simplifying of the expressions can be done first, do it before adding or subtracting

2

5 2

2 15 3

x

x x x

Ideas to keep in mind when adding/subtracting rational

expressions:Make sure the common denominator is the least common multiple of the denominators.

7 3

2 1 2 4

x

x x x x

Ideas to keep in mind when adding/subtracting rational expressions:

If one denominator has a factor of the form a – b and another has the form b – a , only one of these factors needs to appear in the common denominator since they are additive inverses of each other.3 4 1

2 2x x x

HOMEWORK:p. 368 #3-41 odd