#Discrete Math. Check equality according to the laws of operations with sets

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brazen plinth
fallen snowBOT
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upper parrot
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Is the triangle symbol supposed to be the symmetric difference?

upper parrot
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Draw a picture

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That is a good enough proof

brazen plinth
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What picture?

upper parrot
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Usually when you are to prove set theory things it is helpful to draw diagrams

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Like so

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Wait

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Let me give an example

brazen plinth
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I have to write

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And compare then

upper parrot
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Or you can do that

brazen plinth
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The left side is S1 and the right one S2

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I tried but in result nothing

upper parrot
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Ok

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What is the symmetric difference betwene 2 sets?

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What is the definition

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Answer this before you can continue

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Understand every single term in the question

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Before you can tackle it

brazen plinth
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Okay

upper parrot
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Given 2 sets, A and B

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What does A triangle B means?

brazen plinth
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I have some formulas in my copybook

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That's all I've got to use I suppose

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I don't know if I can use other formulas

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That are in internet

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(the language on photo is Ukrainian)

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And I found something like this

upper parrot
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Yes

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THe symmetric difference of 2 sets it's just what they don't have in common,

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( A \ B ) U ( B \ A )

brazen plinth
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Hm

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Can I show you what I wrote?

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And you'll tell me if it's right

upper parrot
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Yes

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Do that please

brazen plinth
upper parrot
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What does that bar above means?

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I never seen this notation before

brazen plinth
upper parrot
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Ok

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Let's seee

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This is my proof

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Yellow is A intersect B

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Blue is A intersect C

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So that means that their symmetric difference ( everything that they DON'T have in common )

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So it's this

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This last picutre symbolises the left hand side, S1 for you

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Now let's try to see what we get when we do S2

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This green is A\B

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This brick color is A \ C

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So their symmetric difference ( The thing that they DON'T have in common ) is this

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Wait

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So this

brazen plinth
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So S1 = S2?

upper parrot
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Yes

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That's all

brazen plinth
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Hm

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But there comes the hard part

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I have to do it with formulas...

upper parrot
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It's the same thing

brazen plinth
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Yes

upper parrot
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It's fine even you don't write it with formulas

brazen plinth
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But the task is to write it

upper parrot
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You can just draw these diagrams what your though process and that's totally fine

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But if you insist

brazen plinth
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Because I have tasks to draw also

upper parrot
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This is S1

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And probably do some other set operation manipulation

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Idk

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good luck

brazen plinth
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+close