Factor Each Expression
Section 8.4
Multiplying and 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. Now,lets go through the steps to simplify a rational expression.
Step 1: Factor the numerator and the denominator completely looking for common factors. Next
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
How do I find the values that make an expression undefined? Completely factor the original denominator.
The expression is undefined when: a= 0, 2, and -2 and b= 0. Factor the denominator
Lets go through another example. Factor out the GCF Next
1 1
Now try to do some on your own.
DAY 2
Remember how to multiply fractions: First you multiply the numerators then multiply the denominators.
The same method can be used to multiply rational expressions
Let’s do another one. Step #1: Factor the numerator and the denominator. Next
Step #2: Divide the numerator and denominator by the common factors
Remember how to divide fractions?
Multiply by the reciprocal of the divisor
Dividing rational expressions uses the same procedure. Ex: Simplify
Now you try to simplify the expression:
Now try these on your own.
Here are the answers: