[理工] [線代] 向量空間

看板Grad-ProbAsk作者 ( )時間13年前 (2010/08/29 22:55), 編輯推噓3(306)
留言9則, 3人參與, 最新討論串1/5 (看更多)
Let R denote the set of all real numbers. If S is a closed and bounded interval in R and contains 0, then S is not a subspace of R. True 請問這題關鍵是在Bounded嗎? 如果是開區間就不是Subspace嗎? The empty set is a vector space over and field. False 這題是因為Field的關係嗎? -- -- ※ 發信站: 批踢踢實業坊(ptt.cc) ◆ From: 61.62.99.36

08/29 23:40, , 1F
1.Subspace一定是開區間 2.zero space是一個點
08/29 23:40, 1F

08/29 23:44, , 2F
更正2.empty set不是vector space @@
08/29 23:44, 2F

08/29 23:49, , 3F
第一題要看他"+"怎麼定義的吧
08/29 23:49, 3F

08/29 23:49, , 4F
如果是普通加法的確是不可能bounded
08/29 23:49, 4F

08/29 23:49, , 5F
若u屬於vector space V ,則u+0(zero vector)=u
08/29 23:49, 5F

08/29 23:50, , 6F
空集合應該不滿足上式這樣...@@
08/29 23:50, 6F

08/29 23:52, , 7F
任何space至少要有zero vector 這樣想應該就可以了
08/29 23:52, 7F

08/29 23:53, , 8F
↑我說第二題
08/29 23:53, 8F

08/30 00:00, , 9F
3F 正解
08/30 00:00, 9F
文章代碼(AID): #1CUdJGX5 (Grad-ProbAsk)
文章代碼(AID): #1CUdJGX5 (Grad-ProbAsk)