# Help me expand this proof to make more sense. (1 Viewer)

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#### uncledub

1. The problem statement, all variables and given/known data

f^-1(Union{Vsub alpha : alpha belongs to Lambda})=Union{f^-1(Vsub alpha): alpha belongs to Lambda}

2. Relevant equations

3. The attempt at a solution

Assume that x belongs to X. Then x belongs to f^-1(Union{Vsub alpha : alpha belongs to Lambda}) iff f(x) belongs to Union {Vsub alpha : alpha belongs to Lambda} iff there exists beta belongs to lambda such that f(x) belongs to Vsub beta iff there exists beta belongs to lambda such that x belongs to f^-1(Vsub beta) iff x belongs to Union{f^-1(Vsubalpha) :alpha belongs to lambda}

Isnt a proof supposed to make it so that the reader can understand it? With all of the iff's it just gets obnoxious. How does this proof work in a way that someone would actually write it?

#### ╔(σ_σ)╝

Use latex. What you wrote is barely readable to me.

#### uncledub

I dont know what latex is in this context. Will MathType paste in here?

#### issacnewton

uncledub, you are learning proofs. its time you learn latex.

#### uncledub

I use computers and I have never learned DOS, or COBOL. And I never will.

I have made websites and I never learned HTML (other than a few simple commands), PHP, etc.

I am not sure what the correlation is between learning proofs and learning latex. When I type up my assignments I use MathType. MathType is insanely easy to use. I am not sure how anyone could expect me to learn a completely different language just so I can type stuff up.

I have never met a high school math teacher who knows latex or even knows what it is. I just want to get through this course. I am not going to be a Math Major. But I do want to take a Math course every once in a while.

#### uncledub

Does this show up?

#### Attachments

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#### issacnewton

Yes I can see that. I am familiar with introductory analysis but the notation here is
confusing. What book is this from ? there are so many 'iff' s there which makes it
confusing

#### uncledub

Introduction to Topology - Baker

The entire book is like this. It is awful. You have to have a Masters in Mathematics to understand it.

#### issacnewton

well uncledub, there are prerequisites of every course. I wouldn't try taking differential
geometry class since I haven't had graduate level real analysis. So have you taken
all the courses which are required before taking this course ?
I think the book your course is using, is not good according to the reviews on
amazon

Code:
[URL]https://www.amazon.com/Introduction-Topology-Crump-W-Baker/product-reviews/1575240084/ref=cm_cr_pr_hist_1?ie=UTF8&showViewpoints=0&filterBy=addOneStar[/URL]

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#### uncledub

This is the introductory course that is given by the math department before any Masters level math courses. I passed all of my Bachelors level classes with flying colors. But it was at a different University so maybe I was short changed in my education. I thought I was going to take my 18 hours of masters level math so I could teach high school concurrent college algebra but I think I am going to stop that and work on other certifications. I just want to make it through.

Now that this assignment is done I can ask the professor to work out the problem so I can see what I should have done.

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