Shirabe
べき 集合
English jmdict
1
noun (common) (futsuumeishi) mathematics power set
Other forms 冪集合 【べきしゅうごう】 · 羃集合 【べきしゅうごう】 (rarely used kanji form) · ベキ集合 【べきしゅうごう】 (search-only kanji form) · 巾集合 【べきしゅうごう】 (search-only kanji form)

可しべし

auxiliary 'ku' adjective (archaic)
English jmdict
1
auxiliary · 'ku' adjective (archaic) formal or literary term word usually written using kana alone must;should;ought to
See also: 可き (べき)
各会員は会費を払うべし。
Each member has to pay a membership fee.
2
auxiliary adjective · 'ku' adjective (archaic) formal or literary term word usually written using kana alone will (surely);be bound to;must
3
auxiliary · 'ku' adjective (archaic) formal or literary term word usually written using kana alone will (do);shall
indicates volition