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can someone pls explain this to me ASAP (1 Viewer)

Anaya R

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a stroke above the letter means *not
AUB means the common stuff between A and B
If the U is flipped then it means the stuff A and B do not have in common
 

011235

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first one for eg is (not A) or B

1660819786535.png
 
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kkk579

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first one for eg is (not A) and B

View attachment 36121
thanks a lot is there a way for me to remember this without actually memorising everything? i mean like i want to understand the actual concepts itself so when i look at the qs i can do it right away without trying to just memorise them. but it confuses me a lot so i don’t rlly understand it
 

011235

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these are just examples. don't memorise them all. the main thing to understand is the notation

U -> union / OR.
for example with AUB think about the area of the venn diagram with A and the area of the venn diagram with B -> its all that area that is covered by A OR B OR both.

∩ -> intersection/AND.
For example with A∩B think about the area of A and B again, but this time, because its the intersection/AND, its only the area covered by both A AND B.

line over -> NOT. Whatever parts the line is over is NOT
For example notA is everything thats not A. If you take the area shaded by A then invert it so everything shaded becomes unshaded and everything unshaded becomes shaded. Thats NOT

then we can combine these. like your notA∩B
Consider the areas of the venn diagram that are NOT shaded by A, and the areas that are shaded by B. What parts are shaded by both of these two areas? That's what notA∩B means.
 

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