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I am needing to make a detailed comparison of the affine conics in $\mathbb{R}^2$ with that of the projective conics in $\mathbf{P}^2$

could only identify:

a) classification of non-degenerate conics

b) single pt given by $x^2 + y^2 = 0$

c) line $xy=0$

(e,f,g) empty set given by $x^2 + y^2 = -1$, $x^2 = -1$ or $0 = 1$

j) parallel lines $x(x-1)=0$

k) double line $x^2 = 0$

l) plane given by $0=0$

Can someone please help on this?

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    Projective over what field?2012-08-23
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    Okay. This looks like homework; what have you tried?2012-08-23
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    possible duplicate of [Cases for distinguishing affine and projective conics of a given field](http://math.stackexchange.com/questions/191773/cases-for-distinguishing-affine-and-projective-conics-of-a-given-field)2012-09-06
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    Please read [$\TeX$ / $\LaTeX$ / MathJax basic tutorial and quick reference](http://meta.math.stackexchange.com/questions/5020/tex-latex-mathjax-basic-tutorial-and-quick-reference).2012-09-09
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    @ZhenLin: I've removed the close flags on this question since its duplicate has been deleted.2012-09-09

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Projectively, all nondegenerate conics over the reals are equivalent. In the affine plane, you can determine whether a conic is an ellipse, a parabola or a conic by counting the points at infinity: hyperbolas have two of them, the parabola one, and ellipses none (no real ones in any case).

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    I edited my problem better so please check it out above. Thanks2012-09-05
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    Franz: I would count $x^2 + y^2 + z^2 = 0$ as a nondegenerate real projective conic. Since it has no real points, it is certainly not projectively equivalent to $x^2 + y^2 - z^2 = 0$. In this standard arithmetic-geometric philosophy, there are precisely two equivalence classes of nondegenerate projective conics over $\mathbb{R}$.2012-09-09