"Kûn (sò͘-ha̍k)" pán-pún chi-kan bô-kāng--ê tē-hng

刪去的內容 新增的內容
'''Kûn''' (Eng-gí: group) chāi sò͘-ha̍k tiong sī chi̍t khoán tài-sò͘ kò͘-chō (algebraic structure), iā chiū sī chi̍t-ê kap sǹg-hoat... ê ia̍h í-keng kiàn-li̍p
 
Tē 6 chōa:
Chim-chiok lâi-kóng, chi̍t-ê kûn "G" nā sêng-li̍p, piáu-sī i sī m̄-sī khang-ê chip-ha̍p, i ū chi̍t thò [[sǹg-hoat]] "•", chia ê chip-ha̍p kap sǹg-hoat ài móa-chio̍k sì-ê tiâu-kiāⁿ:
 
* Ha̍h Hong-pì-sèng (closure): Só͘-ū "G" lāi-té chhìn-chhái kéng ê "a" kap "b" in keng-kòe "a • b" sǹg--chhut-lâi ê kiat-kó mā tī "G" lāi.
* Ha̍h Kiat-ha̍p-sèng (associativity): Só͘-ū "G" lāi-té chhìn-chhái kéng ê "a", "b" kap "c", ū "(a • b) • c = a • (b • c)" koan-hē.
* Ū tan-ūi-goân (identity element): "G" lāi-té ū chi̍t-ê goân-sò͘ "e", kap só͘-ū ê "a" ū "e • a = a • e = a" koan-hē.
* Ū ge̍k-goân (inverse element): "G" lāi-té bí-chi̍t-ê "a", tùi-taⁿ chi̍t-ê tī"G" lāi-té ê "b", in ū "a • b = b • a = e" koan-hē, chia-ê "e" sī téng-chi̍t-hāng kóng ê tan-ūi-goân.