950] ON THE SEXTIC RESOLVENT EQUATIONS OF JACOBI AND KRONECKER. 479
where the terms containing 12, 13, 14, 23, 24, 34 respectively are each =0, viz. the
coefficient of 12 is (- e + e 4 ) + (- e 4 + 1) + (- 1 + e) = 0 : that of 13 is
1 — e 3 -f (e 2 — 1) + (— e 2 + e 3 ) = 0 :
and so for the other coefficients. In like manner it appears that the terms multiplied
by 1, 2, 3, 4 (= os 1 , x 2 , x 3 , # 4 ) respectively are each =0, and thus the equation in
question is verified. And in like manner it is shown that
fo + e [fi + /2 + e 4 / 3 + ~ 0.
The roots / thus satisfy the relations
fo + fi+ f 2 + fs+ / 4 =-/Vo,
fo + e2 /l + ^ fl + e f3 + e? ’fi = 0,
/0 + e 3 fi + efa + e 4 / 3 + e 2 / 4 = 0,
or the equation for / 2 belongs to the class of Jacobi’s multiplier equations. Hence
(see Brioschi’s “Appendice terza” before referred to) the form of the equation is
(/ 2 — a) 6 - 4a (/ 2 — a) 5 + 106 (/ 2 - of — 4c (/ 2 — a) 4- ob 2 - 4>ac = 0,
or determining the arbitrary coefficient v so that a may be =0, the form is
/ 12 + 106/ 6 - 4c/ 2 + ob 2 = 0,
which is Kronecker’s equation
/ 12 - 10 <£/ 6 + 51/r 2 = yjrf\
As to the meaning of the coefficients a, b, c, I recall that, in virtue of the foregoing
linear relations between the roots, these may be expressed in terms of three arbitrary
quantities a 0 , a lt a 2 as follows:
f =a 0 V5,
/0 = + ®1 +
fi = a 0 + ea x + e 4 a 2 ,
/2 = a 0 + e 2 a x + e 3 a 2 ,
/3 = a 0 + e 3 aj + e 2 a 2 ,
/4 = a 0 + e 4 a x + ea 2 ,
and a, b, c are then determinate functions of a 0 , a 1} a 2 , viz. we have
a= a 2 + a x a 2 ,
b = 8a 0 4 aia 2 — 2 a 0 2 a 1 2 a 2 2 + a^aj — a 0 (af 3 + a 2 5 ),
c = 80a 0 6 a 1 2 a 3 2 — 4Oa 0 4 a 1 3 a 2 3 + 5a 0 2 a 1 4 a 2 4 + a^a/'
— a 0 (32a 0 4 — 20a 0 2 a 1 a 2 + ba 2 a 2 ) (a? + a/)
+ l (a a 5 + a 2 5 ) 2 ;
so that, for a = 0 and therefore a 0 = V— a^, we have
6 = lla! 3 a 2 3 — a 0 (a 2 5 + a 2 5 ),
c = — 44a 1 6 a 2 5 — 57a Q a^a 2 (a^ + a 2 5 ) + | (af + a 2 5 ) 2 ,
but I do not know that for Kronecker’s form the actual values of a 0 , a 1} a 2 in terms
of the coefficients of the quintic equation have been calculated.