1350 
- ~ Mtl 
(2) ul F)> 7 i or y” [ug ])°>F f 
To prove that f(5)< O it remains to show that 
ot ee 
2y (VF I] >F { 42s ta 33 
AO ony eal 
Sy Orme eo fetes mes 
or 2 ghee + aa #3 » Which is true. 
aS 
4. Proof of (8d) 
We have 
fil5) 
os vfZ) 
FB) = 0, v(z 
itp = Py» F (3) = 0 and fp) is negative; hence theorem (8d) 
istrue. IfB =5,, fp) is positive and Ale) = 0. 
If Py< P<P,, Riv) is positive while BP) is negative. 
Finally, if Py<P; <p, both AP) and AlP) are positive. 
In this case, however, the factors for the expression FP) 
are each either greater than or equal in absolute value to the 
is es 
