Rational

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Rational Expressions
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Rational Expressions
Rational Expression an expression written in
the form where a variable is in the denominator
Examples

• The Domain of a Rational Expression is all real
  numbers, excluding the values which will make
  the denominator zero.
• Those values that are excluded are said to be
  Restricted from the Domain
• A rational expression is in simplest form if the
  numerator and denominator have no common factors
  except 1 or -1

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Rational Expressions
Simplifying
Simplify , and find all restricted values
Step 1 Factor numerator and denominator Step
2 Cancel like factors Step 3 Find restrictions
for BOTH factors of the denominator What values
will make the denominator zero?
Side problem
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Rational Expressions
Simplifying
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Rational Expressions
Simplifying
Now you try
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Rational Expressions
Multiplying Dividing
To Multiply two rational expressions, we multiply
their numerators and multiply their denominators.
First we cross cancel (pre-reduce), then
multiply
1
x2 6 3y 5x
2
2x 5y
1
1
To Divide two rational expressions, we flip the
second term and multiply
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Rational Expressions
Multiplying Dividing
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Rational Expressions
Multiplying Dividing
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Rational Expressions
Multiplying Dividing
Now you try
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Rational Expressions
Adding Subtracting
To add or subtract rational expressions with the
same denominators, we combine the numerators, and
the denominator stays the same
Example
To add or subtract rational expressions with
different denominators, we have to find the Least
Common Denominator (LCD), before we add or
subtract
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Rational Expressions
Adding Subtracting
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Rational Expressions
Adding Subtracting
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Rational Expressions
Adding Subtracting
Now you try
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Rational Expressions
Adding Subtracting
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Rational Expressions
Fraction Busters Review
Step 1 Find LCD Step 2 Multiply EVERYTHING by
LCD Step 3 Simplify Step 4 Solve like normal
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Rational Expressions
Fraction Busters w/Rational Expressions
Step 1 Find LCD Step 2 Multiply EVERYTHING by
LCD Step 3 Simplify Step 4 Solve like normal
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Rational Expressions
Fraction Busters w/Rational Expressions
Now you try
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Rational Expressions
Fraction Busters w/Rational Expressions
Now you try
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