How Does the Triangle Inequality Apply to Complex Fraction Inequalities?

stokes
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Hello all, I am having some difficulties with a question. Hope you guys can help shine some light on the situation.

Use the triangle Inequality and the fact that 0< |a| < |b| + => 1/|b| <
1/|a| to establish the following chains of inequalities.

|x-2 / x^2+9| "Is less than and equal to" |x| + 2 / 9

Sorry about the display of the question, I really don't know other way to correctly type it.

Please explain your answers, and the reason you use such method to answer this question.

Thanks a lot for your much needed help.
 
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So the triangle inequality is: |x+y| \leq |x| + |y|. We are also given that 0 &lt; |x| &lt; |y| \rightarrow \frac{1}{|y|} &lt; \frac{1}{|x|} and want to establish |\frac{x^{2}}{x^{2}+9}|\leq \frac{|x|+2}{9}
 
Last edited:
stokes said:
|x-2 / x^2+9| "Is less than and equal to" |x| + 2 / 9

Sorry about the display of the question, I really don't know other way to correctly type it.
There's a little trick called "parentheses."
 
Thanks for making the question much more understandable... any help?o:)
 
Please guys need some advice... Thanks.
 
is it |x-2| or |x^2| /{...} ?
 
How big can x^2/(x^2+9) get?
 
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