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Simplifying Rational Expressions: It's Simple

Simplifying Rational Expressions: It's Simple

Author: Nate Muckley

Learn to simplify rational expressions.

It's not "CARD" to learn this principle. You will be able to simplify rational expressions "HANDILY." You'll be "MOVIE"ing through your math levels. Learn the meanings to these puns and how to simplify rational expressions in this packet!

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     A RATIONAL EXPRESSION is an expression without a fraction or a square root

in the numerator or denominator.  It is often expressed as a fraction of polynomials.


 For example:



Simplifying Rational Expressions!

Feel free to turn down the music if you get annoyed by it.

Excluded Values

This is very important!


Back in the video, recall when we factored the denominator to:


(x + 6) (x - 1)


     So this means that if we had x = 1 or x = -6, that set of parentheses

would equal 0, and make the entire denominator = 0




     We can't have the denominator = 0, because then we would have an

undefined expression.


     This means that 1 and -6 are EXCLUDED VALUES;  x-values that

would make the expression undefined.  It's what makes the bottom of the

fraction 0, not the top.  If the top is zero, then the expression IS ZERO,

and not UNDEFINED.

     The real answer to the video is:

     Remember to check for excluded values whenever you simplify

rational expressions!

Practice Problem!

Powerpoint courtesy of Dr. Seth Marx IV

What are the Excluded Values for the problem above?

Scroll down for the answer













they are -5 and -6