Cubic Surfaces Jaap Top - Wiskunde
Cubic Surfaces Jaap Top - Wiskunde
Cubic Surfaces Jaap Top - Wiskunde
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So it is possible to improve Euler’s result!<br />
parametrizations using cubic polynomials were recently found algebraically<br />
by Noam Elkies and geometrically (using the modern<br />
proof of Clebsch’s theorem above) by Irene Polo and me:<br />
x = −a 3 − 2a 2 c + 3a 2 b + 12abc − 3ab 2 − 4ac 2 + 6b 2 c + 12bc 2 + 9b 3<br />
y = a 3 + 2a 2 c + 3a 2 b + 12abc + 3ab 2 + 4ac 2 − 6b 2 c + 12bc 2 + 9b 3<br />
z = −8c 3 − 8ac 2 − 9b 3 − a 3 − 3a 2 b − 3ab 2 − 4a 2 c − 12b 2 c<br />
w = 8c 3 + 8ac 2 − 9b 3 + a 3 − 3a 2 b + 3ab 2 + 4a 2 c + 12b 2 c.<br />
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