[數撚圍爐區] 一唔開post就成班白咭衝哂出去派膠 (82)
膠智的kai龍
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想問下呢題應該點諗 同埋點樣先至叫做 Dense 同 not dense
not dense咪搵到兩個real number中間無佢的element咪得
但都係有幾點唔明
1. 個definition 唔係話 if p, then set B is dense. 咁上面話 if not p, then B is not dense 唔係叫denying the antecedent？
2. 我原先以為 Dense set個definition 係咁理解 fix咗個element b of B，我哋搵唔到兩個real number 冇包住 b 嘅話咁 set B is dense. 之後我諗到如果 b= 1/2 in B, 咁4,5之間冇包住b
即係正確嘅理解係 喺是但兩個real numbers 之間搵到個element of B 咁B就係叫dense set.
3. 可唔可以解釋下個答案 而家仲有啲亂
1. 個definition 唔係話 if p, then set B is dense. 咁上面話 if not p, then B is not dense 唔係叫denying the antecedent？
2. 我原先以為 Dense set個definition 係咁理解 fix咗個element b of B，我哋搵唔到兩個real number 冇包住 b 嘅話咁 set B is dense. 之後我諗到如果 b= 1/2 in B, 咁4,5之間冇包住b
即係正確嘅理解係 喺是但兩個real numbers 之間搵到個element of B 咁B就係叫dense set.
3. 可唔可以解釋下個答案 而家仲有啲亂
