Adding and Subtracting Rational

Expressions

Section 5.3

How do you add or subtract numerical fractions?

You can add or subtract rational expressions the same way.

Review

Adding or Subtracting requires common denominators like numerical fractions

You will need to figure out the LCD by finding the LCM of the denominators

How to find LCM:◦ Factor each polynomial◦ Write any repeated factors as powers◦ LCM is each different factor to its highest

exponent.

Rational Expressions

1) &

2) &

3) &

EX: Find the LCM for each pair

To add or subtract with unlike denominators◦ Find the LCD◦ Rewrite each fraction as an equivalent fraction

over the LCD◦ Check your answers◦ Some answers may be extraneous solutions

Rational Expressions

Add or subtract. Identify any x-values for which the expression is undefined.

1) 2)

3) 4)

5)

EXAMPLES

Contain one or more fraction in numerator, denominator, or both.

What does the fraction bar mean? You can rewrite any complex fraction as

division problem OR You can multiply each term by the LCD of all

fractions

Complex Fractions

1) 2) 3)

4) 5)

EX: Simplify. Assume all expressions are defined.

Day 1: page #17-27, 33-41

Day 2: page #28-30, 43-45, 49-51, Accelerated add: 53-57

HOMEWORK