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| 2013/09/09 17:55:03瀏覽128｜回應0｜推薦0 | |
| Q : 是否存在某數n使 n^4+2n^3+2n^2+2n+1 為完全平方數? A : (1) : 令 n^4+2n^3+2n^2+2n+1 = k (n^4+n^3+n^2)+(n^3+n^2+n)+(n+1) = n^2(n^2+n+1)+n(n^2+n+1)+(n+1) = n(n+1)(n^2+n+1)+(n+1) = (n^2+1)(n+1)^2 (2) : (n^4+2n^2+1)+2n(n^2+1) < (n^2+n+1)^2 = 根據 (１) : k>(n^2+n)^2 |
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| ( 興趣嗜好｜其他 ) |
