Otro
Which Quadric Is Which?
Autor
Fabre, Claude
Resumen
Educação Superior::Ciências Exatas e da Terra::Matemática A quadric surface is the zero set of a quadratic expression in three variables—here, the 3D Cartesian coordinates x, y and z . There are precisely 17 types of quadrics, but some of them are degenerate and others are imaginary. The nonparabolic family is given by [(x²/a²)+i(y²/b²)+j(z²/c²)+d] where i, j and d can be -1, 0 or 1. The parabolic family (which overlaps the nonparabolic family somewhat) is given by [(x²/a²)+i(y²/b²)+kz+d]. This Demonstration shows the chosen polynomial, identifies its type, and plots the zero set. The checkbox toggles between the nonparabolic and parabolic families. All 17 types are represented