SWBAT…simplify rational expressions Wed, 4/3 Agenda 1. WU (15 min) 2. Lesson on rational expressions (25 min)  -6 examples 1.) Factor 7x – 7 2.) Factor 8x – 8 3.) Factor x 2 – 1 4.) Factor x 2 – 9 5.) Factor x 2 – 3x – 10 6.) x 3 + 3x 2 HW#3: Dividing Monomials

Simplifying Rational Expressions

Multiplying &Dividing Rational Expressions  Remember that a rational number can be expressed as a quotient of two integers.  A rational expression can be expressed as a quotient of two polynomials.

Remember, denominators can not = 0.

For what values of x is each rational expression undefined? x = 0 x = -3 x = 1

Step 1: Factor the numerator and the denominator completely looking for common factors. Next Ex. 1

What is the common factor? Step 2: Divide the numerator and denominator by the common factor.

1 1 Step 3: Multiply to get your answer.

Looking at the answer from the previous example, what value of x would make the denominator 0? x = -1 The expression is undefined when the values make the denominator equal to 0

Ex. 2 Ex. 3

1 1 Ex. 4

Remember how to multiply fractions: First you multiply the numerators then multiply the denominators.

Step #1: Factor the numerator and the denominator. Next Ex. 5

Step #2: Divide the numerator and denominator by the common factors

Step #3: Multiply the numerator and the denominator.

Multiply by the reciprocal of the divisor Remember how to divide fractions?

Dividing rational expressions uses the same procedure. Ex. 6: Simplify

Do HW#6 Problems 1 – 10 FYI: All problems were taken from college math placement tests

Additional Examples: Ex. 7 Ex. 8 Ex. 9

Answers: