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You are not logged in. #1 20090418 21:33:01
Kurre's Exercises#1 Solve: b) #2 Find all functions satisfying: #3 Find all functions satisfying: #4 Find all functions satisfying: #5 Let a be a given real number. Find all functions satisfying: #6 Find all injective functions satisfying: Last edited by Kurre (20090506 03:21:26) #2 20090505 04:45:12
Re: Kurre's ExercisesWell I would like to change the topic to "kurres exercises" or something, but I cant, so here comes a few more that are not related to functional equations. Find expressed in A #8 Let H be a subgroup of G. prove that the following statements are equivalent: a) H is a normal subgroup b) for all a,b in G, if and only if #9 Solve the following equation in primes p,q,r: Last edited by Kurre (20090507 00:07:52) #3 20090505 06:50:47
Re: Kurre's ExercisesChanged! You can edit a topic's title by editing its first post. Why did the vector cross the road? It wanted to be normal. #4 20090505 08:30:08
Re: Kurre's ExercisesThanks! But I still cant find a field where to edit the title? i know what u mean, i have seen it before. I thought it had been too long since i created the topic.. #5 20090505 09:03:26
Re: Kurre's ExercisesHmm. Maybe the software has changed then. I'm certain it used to be possible that way. Why did the vector cross the road? It wanted to be normal. #6 20090505 18:50:17
Re: Kurre's Exercises
You can edit a thread title for something like the first five minutes after you start the thread; after that period, you can’t edit the title any more (except for moderators). #7 20090505 21:29:08
Re: Kurre's ExercisesThanks for clarifying! Why did the vector cross the road? It wanted to be normal. #8 20090507 00:18:20
Re: Kurre's Exercisescorrect mathsy hints Last edited by Kurre (20090507 00:20:42) #9 20090507 04:16:44#10 20090507 04:54:14
Re: Kurre's Exercises
Why did the vector cross the road? It wanted to be normal. #12 20090507 06:27:55#13 20090507 06:52:51
Re: Kurre's Exercises#10 let f be a function from the natural numbers to the natural numbers satisfying if n1>m>0. Find the least possible value of f(2009) and f(2011)Last edited by Kurre (20090507 06:55:34) #15 20090508 03:18:05
Re: Kurre's Exercises#11 Find all functions from the positive rational numbers to the positive rational numbers satisfying: Last edited by Kurre (20090508 03:28:36) #16 20090508 22:15:18
Re: Kurre's Exercises#12 and determine when equality occurs. Last edited by Kurre (20090508 22:15:34) #17 20090513 01:33:32
Re: Kurre's ExercisesHi Kurre; In mathematics, you don't understand things. You just get used to them. I have the result, but I do not yet know how to get it. All physicists, and a good many quite respectable mathematicians are contemptuous about proof. #18 20090516 06:12:30
Re: Kurre's Exercises
Im really glad to hear you are working on it #19 20090516 06:26:45
Re: Kurre's Exercises#13 Let M be a (p1)x(p1) matrix where p is an odd prime number and each row has each element from {1,2,3,...,p2,p1} exactly once. Prove that pdet(M) Last edited by Kurre (20090516 07:13:12) #20 20090516 07:07:22
Re: Kurre's Exercises#13 is false for p=2. Why did the vector cross the road? It wanted to be normal. #21 20090516 07:15:43
Re: Kurre's Exercises
true, forgot about that. Fixed! #22 20090516 17:46:48
Re: Kurre's Exercises
can be generalized. For each integer , divides the determinant of a matrix in which each positive integer less than and coprime with appears exactly once in each row and in each column.
#23 20090516 21:15:07
Re: Kurre's Exercises
Yea I realized that when trying to sleep yesterday :p Last edited by Kurre (20090516 21:18:45) #24 20090517 00:48:54
Re: Kurre's Exercises#14 ? #25 20090517 09:05:43
Re: Kurre's ExercisesIncomplete answer so everyone else please continue to look Last edited by bobbym (20090517 09:11:55) In mathematics, you don't understand things. You just get used to them. I have the result, but I do not yet know how to get it. All physicists, and a good many quite respectable mathematicians are contemptuous about proof. 