moongazer
What is the meaning of "or" , "and" in math?
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moongazer
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and what do you call those?
UnkleRhaukus
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a or b (inclusive)\[a\vee b\]
a and b
\[a\wedge b\]
UnkleRhaukus
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|dw:1348403720368:dw|
UnkleRhaukus
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|dw:1348403767690:dw|
UnkleRhaukus
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|dw:1348403820405:dw|
moongazer
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what do you call those "and" "or"
UnkleRhaukus
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Conjunction \wedge \(\wedge\)
Disjunction \vee \(\vee\)
moongazer
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thanks, can you help in finding a domain of a function?
UnkleRhaukus
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Negation \neg \(\neg\)
|dw:1348404218012:dw| \[\neg C\]
UnkleRhaukus
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what is your function?
moongazer
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|dw:1348405394804:dw|
UnkleRhaukus
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factorise the numerator and denominator
moongazer
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btw, "or" is like the union of the set and "and" is like the intersection of a set.
Is that correct?
moongazer
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|dw:1348405630353:dw|
moongazer
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@UnkleRhaukus
UnkleRhaukus
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"or" is like union
"and" is like intersection
kinda but they are used for slightly different things,
i think
the logic symbols are used for points,
where as the set symbols are used for sets of points
UnkleRhaukus
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what is the only number that dosent make sense in a denominator ? ,
what are two point values for x that would make your function undefined ?,
exclude these from your domain
moongazer
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{x|x>2 and x>3 and x>=5 and x>=4}
is this correct?
moongazer
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@UnkleRhaukus
UnkleRhaukus
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i get \[\{x|((x≠2)\wedge (x≠3))\}\]
UnkleRhaukus
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hmm im not right though
moongazer
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The answer in my notebook says: dom K: {x|x<2 or 3<x<=4 or x>=5}
I only copied that from my classmate because I was absent when my teacher discussed this.
so I don't know how they got that
UnkleRhaukus
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there is a strange discontinuity where 4<x<5
moongazer
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my notes also says that "use the number line to graph the values for which the function is defined.
moongazer
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that is for finding the domain.
moongazer
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@UnkleRhaukus
UnkleRhaukus
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well x is defined from -∞ to 2 , at 2 this is a discontinuity, the from 2 to 4 defined, then discontinuity from 4 to 5 then defined again from 5 to ∞