Rational Expressions: Solving Homework with Difficulty

AI Thread Summary
The discussion focuses on solving the rational expression x² + x - 30 over x² - 3x + 2 and identifying when it is undefined. The key point is that a rational expression is not defined when the denominator equals zero. Participants emphasize the importance of factoring the denominator, x² - 3x + 2, to find the values of x that make it zero. The solution involves determining the roots of the trinomial, which can be found through factoring. Understanding these concepts is crucial for solving similar problems effectively.
Annie_D
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Homework Statement


x (squared) + x - 30
_____________________
x (sqaured) -3x + 2

Find all numbers for which the rational expression is not defined.

i know this is really easy stuff, but i have a hard time staying focused in math, and i have to always teach myself with the book, but sometimes the book isn't very informative.

I have the answer, but don't know how to go about doing these problems. I know you like people to attempt them, but i don't even know where to begin after factoring the 30 .
 
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When is a rational expression (a fraction) not defined? For what value is division impossible?
 
0, i got in now though. thanks anyway.
 
So for what x will x2 - 3x + 2 = 0? You need to factor this trinomial to answer that question.
 

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