432 
of variable from f~ to CO” and 72’ in the integral of Eq. 5.12, use 
of Eq. 5.9, and substitution in Eq. 5.10 yields, after an integration by 
wie 
, ao ae 
et | 26,00) Gulla) yg! 4 GIT) -6, 
Pa Be" 5 inagye * lt) Catto), 
’ f 
= | AT a peered 2 
=) =a ee Oe ca eit fog =& 
Je (3 | ier - Zay 22, 2 ER Ny 
P57) (o-') F 
C1) 
23/ To obtain Eq. 5.13 we proceed as follows. From Eq. 5.9 we get by 
differentiation : 
ay / 
eee iiGes te BAT ny at Woh Geta See: 
66 (1480) lo or litpo 
Employing this result together with Eq. 5.8 for U_ in kg. 5.12, 
we obtain 
: | a dt 
fee aei\| Cal 
(fii 
a oli po)? 
G 
pies ae ] 
~ &(%) a (itac)” o'(i +Bo')® 
G, 
Integration of the last term by parts, division of the interval of 
integration in the second term 
‘a ie ie 
o~ T— is 
and partial integration of the term 
| q 
o- 
45 
yields Eq. 5.13. 
