HELP I solving a set problem

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The discussion revolves around solving a set theory problem involving subsets. The user seeks assistance in determining the relationships between specific pairs of sets, A-B and A-(B-C), as well as AUB and (AUB)-Ø. Forum members emphasize the importance of showing prior attempts to solve the problem and suggest using Venn diagrams as a helpful visual tool. The user expresses uncertainty about how to begin the problem and requests guidance. Engaging with the community for support is encouraged to clarify these set relationships.
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HELP! I need help solving a set problem

12) For each of the following pairs of sets, explain which is a subset of the other. If neither is a subset of the other, explain why.

a) A-B and A-(B-C)
b) AUB and (AUB)-Ø
 
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jmwilson11268 said:
12) For each of the following pairs of sets, explain which is a subset of the other. If neither is a subset of the other, explain why.

a) A-B and A-(B-C)
b) AUB and (AUB)-Ø
Hello jmwilson11268. Welcome to PF !

What have you tried?

Where are you stuck?

According to the rules for the Homework Help section of this Forum:
... NOTE: You MUST show that you have attempted to answer your question in order to receive help. You MUST make use of the homework template, which automatically appears when a new topic is created in the homework help forums.
 


I don't know how to start this problem. I just need a little push in the right direction.
 


jmwilson11268 said:
I don't know how to start this problem. I just need a little push in the right direction.
Draw a Venn Diagram for each.
 


Okay. Thanks!
 
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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