In) el EEEN 
VEN en p=tVi , B= sk 
ze Hi Ien») , Po Lah ed 
ak va sn(v) BE en») 
ik PEROT ees La 
IV aye Ln ao 
eo ere ee 2A 
144? woh | 
= Ld en( on(v) + dn(w) oe Ee on(v) +-dn(v) IK (84) 
ie aco Vn Dane) Toe ek US eno) 
V1 en 6 VIN? en») A Viti 
ag ba i temo a Teen: 
IVI „VIN 
Tae ee VTA 
(4(144") dal») ; V1+A? en(w) 
>= —__—_.. ien nek 
À sn(v) A sn°(v) 
Let us restrict ourselves to real points (z,y) of the conic, then 
follows from (78) that Va,,4.§ must always be real. 
Case II (in which 2 is real) appears only with the hyperbola for 
which holds A,,< 0; so we have here 
2 22 A2 
fy ee Dinie A sat A <0. 
(ee ae © 
From this ensues that in case II we shall find & always imaginary, 
{1 + en (p)} dn (v) 
sn” (v) 
Case IV is found with the hyperbola as well as with the ellipse. 
As here too 4 is real we find 
IVa. with the hyperbola (A,, <0) a,,4 <0, so 5 is imaginary or 
en (v) + dn (v) 
sn* (vp) 
and therefore 
is real ; 
real 3 
en 2 + dn (v) 
IVA. with the ellipse (A,, >0) a,, > 0, so 5 is real and ———— (0) 
p 
is purely imaginary. 
Also case VI appears with the hyperbola as well as with the 
ellipse. On account of 4 being purely imaginary, thus 4? negative, 
holds : 
Vla. for the hyperbola (A,,< 0) a,, 4 >0, hence 5 real, and 
en en (v) 
‘eal : 
EN real ; 
