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You are not logged in. #1 20051122 03:57:02
proof of the sum of squaresI was reading proofs for the exact area under a curve, (as the number of rectangles increases without bound) and right out of no where they replaced a sum of n squared integers into a differant expression and simply said "since 1^2 + 2^2 + 3^2 +... + n^2 = n(n + 1)(2n + 1)/6." Uh... it does? I'm certain they never told me that before. I'd remember something that cool. I thought maybe they'd explain it later when I learn about definite integrals, but they just mentioned it as if I already knew it. Never heard it before. Last edited by mikau (20051122 03:57:58) A logarithm is just a misspelled algorithm. #2 20051122 05:02:08
Re: proof of the sum of squaresYes, it does. You can try proving it by induction. Last edited by kylekatarn (20051122 05:15:51) #5 20051123 04:05:57
Re: proof of the sum of squaresI found a proof in my maths book. I tried scanning and uploading it, but that didn't seem to work. Why did the vector cross the road? It wanted to be normal. #6 20051123 08:08:54
Re: proof of the sum of squares
Mathematical Induction provides proofs... #7 20051123 08:54:14
Re: proof of the sum of squares
True, but I think that my book's proof is quite elegant, with all the cancelling out on the righthand side. Plus, I'd had a hard day at school, so I didn't want to think.
Also true. The proof by induction would go something like this:
Well, he did... Why did the vector cross the road? It wanted to be normal. #8 20080501 21:17:52
Re: proof of the sum of squareshi,could you please help me? 