[微積] 連續性
Let f:[1,2]->R be the function given by
c
0 ,if x in [1,2]^Q
f(x)={
1/n ,if x in [1,2]^Q and x=m/n
m,n are natural numbers , f(1)=1
(1)
Prove that if ε>0 ,then the set {x in [1,2]:f(x)>ε}
has only a finite number of points.
(2)
Prove that f:[1,2]->R is continuous at each irrational number in [1,2]
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◆ From: 140.113.25.222
※ 編輯: suzzdicon 來自: 140.113.25.222 (10/19 02:54)
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10/19 14:33, , 1F
10/19 14:33, 1F
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