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You are not logged in. #1 20120818 17:10:36
The real numbers  ProofProve that for all real numbers x>=1, #2 20120818 17:16:21
Re: The real numbers  ProofHi Shahana; The attempt to prove x>=1 will be difficult. What about x =  1? 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. #4 20120818 17:19:40
Re: The real numbers  ProofHi; 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. #8 20121119 12:43:01
Re: The real numbers  ProofHi; 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. #10 20121119 12:48:56
Re: The real numbers  ProofHi; 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. #12 20121119 12:58:28
Re: The real numbers  ProofHi; 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. #14 20121119 13:07:23
Re: The real numbers  ProofHi; 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. #15 20121119 13:12:20
Re: The real numbers  Proof
There is a minor flaw in this proof. You are using the second case for all x>=1, when you should be using it for x in [2,infty). The limit operator is just an excuse for doing something you know you can't. “It's the subject that nobody knows anything about that we can all talk about!” ― Richard Feynman “Taking a new step, uttering a new word, is what people fear most.” ― Fyodor Dostoyevsky, Crime and Punishment #16 20121119 13:14:42
Re: The real numbers  ProofHi; 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. #17 20121119 13:19:12
Re: The real numbers  ProofThe first case is for reals in [1,2) because that is where x2 is positive. Only for larger numbers should the second case be used. The limit operator is just an excuse for doing something you know you can't. “It's the subject that nobody knows anything about that we can all talk about!” ― Richard Feynman “Taking a new step, uttering a new word, is what people fear most.” ― Fyodor Dostoyevsky, Crime and Punishment #18 20121119 13:37:10
Re: The real numbers  ProofHi; 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. #19 20121119 13:39:33
Re: The real numbers  ProofNo, no. The inequality comes down to x>=6/7 only for x>=2. To prove it for 1<=x<2 you have to use the case where you get x>=6. The limit operator is just an excuse for doing something you know you can't. “It's the subject that nobody knows anything about that we can all talk about!” ― Richard Feynman “Taking a new step, uttering a new word, is what people fear most.” ― Fyodor Dostoyevsky, Crime and Punishment #20 20121119 13:47:48
Re: The real numbers  ProofHi; 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. #21 20121119 13:56:55
Re: The real numbers  ProofFirst we need to split the problem into two cases. The limit operator is just an excuse for doing something you know you can't. “It's the subject that nobody knows anything about that we can all talk about!” ― Richard Feynman “Taking a new step, uttering a new word, is what people fear most.” ― Fyodor Dostoyevsky, Crime and Punishment #22 20121119 16:53:53
Re: The real numbers  ProofHi! Writing "pretty" math (two dimensional) is easier to read and grasp than LaTex (one dimensional). LaTex is like painting on many strips of paper and then stacking them to see what picture they make. 