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You are not logged in. #1 20091228 04:50:25
Fumble and Botch strike again.Hi; Prove that: Has no solution in integers: Proof: 8x^2 is congruent to {0,2,5,8} mod 9 270y^4 is congruent to 0 mod 9 So 8x^2 + 270y^4 is congruent to {0,2,5,8} mod 9 While 210 is congruent to 3 mod 9: So 8x^2 + 270y^4 = 210 has no solutions in integers. Total garbage! What is wrong with this? 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. #2 20091228 06:15:15
Re: Fumble and Botch strike again.As far as I can tell the proof is sound. The statement is certainly true, and here's a simpler way of showing it: Why did the vector cross the road? It wanted to be normal. #3 20091228 06:23:25
Re: Fumble and Botch strike again.Hi;
That is exactly what is wrong with it. Lot of typing no thinking. 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 20091228 08:26:34
Re: Fumble and Botch strike again.
and and so for the equation to have any solution, we must have . That means , which means and so . Then the LHS would be divisible by 9 whereas the RHS isn’t.
Last edited by JaneFairfax (20091228 08:26:54) #5 20091228 11:52:17
Re: Fumble and Botch strike again.Hi Jane; 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. #6 20091229 03:56:35
Re: Fumble and Botch strike again.There is nothing wrong with mods; I use them a lot too. But I also like to keep my mind open for simple solutions, if they exist. #7 20091229 17:49:13
Re: Fumble and Botch strike again.Hi Jane; 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. 