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⋂

n∈N

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⋂

n∈N

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(R,T ) /6/ ()* :4%4&4A)+ 6;$2 4&3656/6 =89:.*)/);K

T ∈ T ⇐⇒ (∀x ∈ T )(∃(a, b) ⊂ T : x ∈ (a, b)

L6 6;$23$ ()* T +,-.9)/)/ $1'+ 4&-$9' )1)/ =.*.+&) D. 2.:.*&) +4@6&C T2. $): 0.* /4+:$2' )1.*./ $1'+ ()* $*$&'+ +$%9$-$9'3'*" L6 6;$2$ R ,;.B

*)/3.+) !"# $%&#"!'( #)*)")+, 3./)&)*" L6 :4%4&4A)C 26+$*'3$ :$/'-&$/$/

E?$F :4%4&4A)9)3)*" L6 :4%4&4A)2) )&.*)3. ($@+$ 28/:.-&.*&. 3. +6*$H$5';"

L6C =89:.*)24* +)C ()* +,-. ,;.*)/3. $2/' :4%4&4A) M$*+&' 28/:.-&.*&.

+6*6&$()&)*"

II" R ,;.*)/3.+) -6:&$+ :4%4&4A)2. =8*. R /)/ $1'+ 4&3656/6 =89:.*)/);"

IN" R ,;.*)/3.+) -6:&$+ :4%4&4A)2. =8*.C 0.* b =.*1.& 9$2'9' )1)/C (−∞, b)()1)-)/3.+) $*$&'+&$*'/ $1'+ 4&3656/6 =89:.*)/);"

I " R ,;.*)/3.+) -6:&$+ :4%4&4A)2. =8*.C 0.* a =.*1.& 9$2'9' )1)/C (a,+∞)()1)-)/3.+) $*$&'+&$*'/ $1'+ 4&3656/6 =89:.*)/);"

IO" (R,T ) )1)/3.+) 0.* $1'+ (a, b) $*$&'5'/'/ +./$* /4+:$&$*' +,-.9) ∂A =[a, b] +$%$&' $*$&'5'3'*" 789:.*)/);"

IP" (R,T ) )1)/3. Q *$924/.& 9$2'&$* +,-.9)/)/ +./$* /4+:$&$*' +,-.9)

∂Q = R 3)*" 789:.*)/);"

IQ" (R,T ) 6;$2' )1)/3. ()&.@)-&.*) +$%$&' 4&-$2$/ ()* +$%$&' +,-.&.* 3);)9)

+6*6/6;"