18
ON CERTAIN DEFINITE INTEGRALS.
[3
j dr u )
Substituting this value, also / + + g-th 2+ •' • j ^ or i n va -l ue of U,
and observing that m — 0 gives % = oo, m = 1 gives % = £, where £ is a quantity
determined as before by the equation
a 2 b 2 t _ 1
F+A s + f + V + "' _ ’
we have
tó, ..Va ft ^{f + V "\ d ?
r(in) J„(f+A’W{(f+TT<£ +A,*)•••]’
or writing (f> + £ for di;' = d(f>, the limits of 0 are 0, » ; or, inverting the limits and
omitting the negative sign,
-M, .„-■**» r •Of + fr l + <i + g4/i, s + 0 + -"| ri *
T (^n) Jo (£ + /¿ 2 + <£) V[(£ + + 0) (£ + h 2 + (f>)...{ ’
which, in the particular case of n = 3, may easily be made to coincide with known
results. The analogous integral
JJ... (n times)
f% + h + ' t \ dxdy ”‘
{(a-x) 2 +(b- y y...r
is apparently not reducible to a single integral.