jnctions. [578
125
578] a MEMOIR ON THE TRANSFORMATION OF ELLIPTIC FUNCTIONS.
sin a= 0, 8 = 0; the
21. As regards the non-existence of the factor il-1, I further verify this by
writing in the equations 0 = 1; they thus become
k s oi- = 8\
k (2ay + 2 a/3 + /3 2 ) = 7 2 + 2y8 + 2 /38,
y 2 + 2/3y + 2a8 + 2/38 = k (2ay + 2/3y + 2aS + /3 2 ),
8 2 + 2y8 = k 3 (a 3 + 2 a/3),
which it is to be shown cannot be satisfied in general, but only for certain values of k.
Reducing the last equation, this is y8 = tea/3, which, combined with the first, gives
ay = /38\ and if for convenience we assume a = l, and write also 6 = + \/k (that is, k = 6~),
then the values of a, [3, y, 8 are a = 1, /3 = yd~ 3 , 7 = 7, 8 = 6 3 ; which values, substituted
in the second and the third equations, give two equations in y, 6\ and from these,
eliminating y, we obtain an equation for the determination of 6, that is, of k. In fact,
the second equation gives
& 2 (2y + 2yd 3 + y-6~^) = 7 2 + 2yd 3 + 2y ;
= ka, 8 = kß ; in fact,
or, dividing by 7 and reducing,
that is,
7 (1- 0 4 ) = 2d 3 (6 2 -1) (d- -0 + 1),
7 (1 + 0 3 ) = — 20 3 (0 3 -0 + 1),
or, as this may also be written,
(7 + 0 3 ) (1 + d-) = - d 3 (d — l) 2 ,
that is,
Moreover the third equation gives
dentically; and these
the factor {(il, l) 4 }.
have P = a (1 + kx 2 ),
alue
y- + 27 2 0“ 3 + 2d 3 +2y = 0 2 (2 7 + 2y"d~ 3 + 20 3 + y 3 d 6 ),
7 2 ( 0 4 — 20 3 + 20 — 1) — 2 (7 + d 3 ) d 4 (d 2 - 1) = 0 ;
whence also
-2d 7
Also
? 2= >~+r
40 6 (0 2 — 0 + l) 2 = 7 2 (d 2 + !) 2 ,
) or 8 = 0 reduce the
shows that if either
we have then the
mation.
wherefore
2(0»- 0 + 1) 2 = -0(0 2 + l) or 2 (d 2 - d +1) 2 + d(d' 2 +1) -0,
d (d 2 + l) 2 + 2 (0 2 — 0 + l) 2 = 0,
2d 4 — 3d 3 + 6d 2 -3d+ 2 = 0,
(2d 2 — d +1) (d 2 — d + 2) = 0.
or
that is,
or finally
1 = 0 or ß = 0, 7 = 0,
LCtOr n — 1.