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某有理参数旋转曲面的隐式方程

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青青子衿 Posted at 2019-3-28 20:06:43 |Read mode
\begin{cases}  
\begin{split}      
x&=&-&\dfrac{(2s-1)(2t^3-3t^2+4)}{2(2 s^2-2s+1)}\\      
y&=&-&\dfrac{s(s-1)(2t^3-3t^2+4)}{2 s^2 - 2 s + 1}\\   
z&=&-&\dfrac{3(t^3-9t^2+18t-12)}{40}   
\end{split}  
\end{cases}
\begin{gather*}
324\bigg(x^2+y^2\bigg)\bigg(1600z^2+6900z+3x^2+3y^2+1197\bigg)^2\\
=\bigg(128000z^3-306000z^2+2160x^2z+2160y^2z-120960z-11745x^2-11745y^2-11124\bigg)^2
\end{gather*}
参见《计算机代数(第二版)》王东明;夏壁灿;李子明
[M]清华大学出版社 2007 P186  Grobner基的应用

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orzweb111 Posted at 2019-3-30 01:18:55
回复 1# 青青子衿

What is this about?

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hbghlyj Posted at 2021-10-23 17:33:29
回复 2# orzweb111
应该是将参数$s,t$消去的算法

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hbghlyj Posted at 2023-2-19 04:39:07
Asymptote: HTML format

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2025-4-21 14:24 GMT+8

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