Modulus Inequality Help: Solving |x/2 + 3| > 3-x^2 and |e^x/2 - 3| > 3-e^(2x)

AI Thread Summary
The discussion centers on solving the modulus inequalities |x/2 + 3| > 3 - x^2 and |e^x/2 - 3| > 3 - e^(2x). The first inequality was solved, but the connection to the second inequality was unclear to participants, leading to speculation about a possible typo in the question. One participant suggested substituting u = e^x, transforming the second inequality into a similar form, but found it unhelpful. Ultimately, the correct substitution proposed was u = -e^x, which provided a clearer path to the solution. The conversation highlights the challenges in linking the two inequalities effectively.
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Homework Statement


Solve | \frac{x}{2} +3 | > 3-x^2
Hence, solve | \frac{e^x}{2} -3 | > 3-e^{2x}


Homework Equations





The Attempt at a Solution



I've solved the first part. But I have no clue what is the link to the second part?! could there be just typo to the question?? I can't find any links...
 
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Let u=e^x

and it becomes

|\frac{u}{2} +3 | > 3-u^2
 
Didn't help.

Anyway I figured the solution already.

should be let u= - e^x
 
I tried to combine those 2 formulas but it didn't work. I tried using another case where there are 2 red balls and 2 blue balls only so when combining the formula I got ##\frac{(4-1)!}{2!2!}=\frac{3}{2}## which does not make sense. Is there any formula to calculate cyclic permutation of identical objects or I have to do it by listing all the possibilities? Thanks
Since ##px^9+q## is the factor, then ##x^9=\frac{-q}{p}## will be one of the roots. Let ##f(x)=27x^{18}+bx^9+70##, then: $$27\left(\frac{-q}{p}\right)^2+b\left(\frac{-q}{p}\right)+70=0$$ $$b=27 \frac{q}{p}+70 \frac{p}{q}$$ $$b=\frac{27q^2+70p^2}{pq}$$ From this expression, it looks like there is no greatest value of ##b## because increasing the value of ##p## and ##q## will also increase the value of ##b##. How to find the greatest value of ##b##? Thanks
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