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You are not logged in. #1 20080721 16:38:52
Find all functionsFind all functions f: (0,∞) (0,∞) such that #2 20080721 19:23:02
Re: Find all functionsI suspect f has to be linear. If so, let , and you’ll find that there are only three possibilities: , , .I don’t know if f can be nonlinear (though I have a hunch that it can’t). #3 20080723 05:19:53
Re: Find all functionsAlso So f must be injective. That’s another thing we can say about the function. #4 20080724 02:40:36
Re: Find all functionsthank you jane Last edited by tony123 (20080724 02:49:41) #5 20080724 03:09:31
Re: Find all functionsYou’re right. I just noticed that f is from to rather than to , so and will not work. 