190 ON SKEW SURFACES, OTHERWISE SCROLLS. [339
where II denotes the product of the terms belonging to all the triads of the m roots,
the result will be symmetrical in regard to all the roots ; and replacing the symmetrical
functions of the roots by their values in terms of the coefficients, we have the required
relation between (ft t), ft &>).
II contains £ [m] 3 terms, whereof |[m — l] 2 contain the ra-thic functions (A 1} B 1} C x , A)
of the root 0! ; that is, the form of II is
(A, fx, v, p)è [w]! (0 1} 1)W(U, l)* [m]3 .. ;
or, when the symmetrical functions are expressed in terms of the coefficients, the form is
(A, fx, v, p)èM 3 (f, 7], ft, <w)£ [m]3 .
Now the above-mentioned determinant is divisible by (0 3 — 0») (0i — 0 3 ) (0*— 0 3 ), or IT is
divisible by II - ft) - 0 3 ) (0., - ; and since this product contains (3x|[m] 3 =)|[m] 3
linear factors, and the product Ç(0 X , 0 2 ,...0 m ) of the squared differences of the roots
contains (2x| [m] 2 =) [m] 2 linear factors, so that we have
where
and consequently
n (0 1 - 0 a ) (0\ - 0 3 ) (0 2 - 0 3 ) = {£ (0„ 0 2 , .. 0 m )}i^»,
Ç(0 1} 0,, .. 0 m ) = Disct. = (ft 77, ft w) 2(m_1) ,
n(ft-00(ft-*.)(*.-*.)-(£ v, ft «) [m " 1]2 ,
so that, omitting this factor, the remaining factor of II is of the form
(A, fx, v, p)i [m]3 (|, y, ft ;
but the determinant vanishes if
A, fx, v, p = (A u B 1} C 1} A), (A%, A, G,, A), (A 3 , B 3 , C 3 , A),
(A, fx, v, p) = (A, B, G, D), 0 = 0 lt 0,, or 0 3 ;
it follows that the product II contains the factor
(A£ + pci] + + pco) ;
or omitting this factor, and observing that
i [w] 3 - [m - l] 2 - £ [m] 3 = £ [m] 3 - [m - l] 2 = £ [m - l] 3 ,
the remaining factor is of the form
(ft v, ft «) itw_1]3 ;
or we have finally
$ (m 3 ) = i [m — l] 3 ,
which is the required expression.