[函數] onto 和one to one
※ [本文轉錄自 trans_math 看板 #1DS70CsT ]
作者: immortal8305 (immortal) 看板: trans_math
標題: [函數] onto 和one to one
時間: Fri Mar 4 12:52:25 2011
Let f and g be function from R to R and f。g(x)=x， ∀ x∈R
(a) Prove or disprove that f is one-to-one
(b) Prove or disprove that f is onto
(c) Prove or disprove that g is one-to-one
(d) Prove or disprove that g is onto
答案是bc成立
為什麼a不成立阿
f(g(x))=x，f(g(y))=y 且x不等於y 這樣不能證明f是1對1嗎
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◆ From: 114.38.116.186
※ 編輯: immortal8305 來自: 114.38.116.186 (03/04 13:36)
※ 編輯: immortal8305 來自: 114.38.116.186 (03/04 13:37)
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