%% PhS
%% fig_conique_03

40 setxunit
0 10  setxrange
-3.5 3.5 setyrange


/H1 {0 0} def
/H2 {9 0} def
/V1 {2 -3} def
/V2 {2 3.2} def
/K {2 0} def
/F {5 0} def
/D {1.8 -3} def
/p {2} def
/e {0.7} def

/rhox {settvar t cos e mul neg 1 add 1 exch div p mul t cos mul} def
/rhoy {settvar t cos e mul neg 1 add 1 exch div p mul t sin mul} def

/Mx {60 rhox 5 add} def
/My {60 rhoy} def
/M {Mx My} def
M point

/H {M V1 V2 orthoproj} def
H point


continu
[K F] points
[H1 H2] ligne
[V1 V2] ligne
[M F] ligne
[M H] ligne



40 320 settrange
{rhox 5 add} {rhoy} courbeparam

rouge
[F 6 0] ( ->) ligne
[F 5 1] ( ->) ligne
H2 F M 1.5 (->) tripointarc

bleu

setTimesItalic
   (K) K dltext
   (F) F dtext
   (D) D ltext
   (M) M uctext
   (H) H cltext
		  
<tex>
$ \Delta $
</tex>
(x) 7.5 0 [1.5 dup] dctexlabel

rouge
<tex>
$ \theta $
</tex>
(x) 6.6 0.7 [1.5 dup] uctexlabel