[712
713]
29
gaiithin and
nsider three
ts 1, 2, 3 ;
he equation
t, the three
the inter-
my eight of
713.
ADDITION TO MR ROWE’S MEMOIR ON ABEL’S THEOREM.
[From the Philosophical Transactions of the Royal Society of London, vol. 172, Part in.
(1881), pp. 751—758. Received May 27,—Read June 10, 1880.]
In Abel’s general theorem y is an irrational function of x determined by an
equation ^ (y) = 0, or say % (x, y) = 0, of the order n as regards y : and it was shown
by him that the sum of any number of the integrals considered may be reduced to
a sum of 7 integrals ; where 7 is a determinate number depending only on the form
of the equation y (x, y) = 0, and given in his equation (62), [Œuvres Completes, (1881),
t. I. p. 168] : viz. if, solving the equation so as to obtain from it developments of y
in descending series of powers of x, we have*
Vl\
Hj/ij series each of the form y = af-' + ...,
n 2 p 2
y = of* + ...,
WjbMfc
y = +
* The several powers of x have coefficients: the form really is y = A l x >L ' + ..., which is regarded as
l
representing the ¡x x different values of y obtained by giving to the radical each of its values, and
the corresponding values to the radicals which enter into the coefficients of the series: and (so understanding
it) the meaning is that there are 11 s such series each representing ¿4 values of y. It is assumed that the
l
series contains only the radical x 1 *', that is, the indices after the leading index 1 are
Jilj - 1 9JÌJ - 2
, ... ; a
Mi Mi Mi
series such as y = A 1 x* + B 1 x% +..., depending on the two radicals x x , x° represents 15 different values, and
would be written y=A 1 x^% +..., or the values of m 1 and y x would be 20 and 15 respectively: in a case like
this where — is not in its least terms, the number of values of the leading coefficient A, is equal, not to
Mi
H 1 . but to a submultiple of . But the case is excluded by Abel’s assumption that —, are fractions
each of them in its least terms.