Then 
Te 
ie = F(t) O(t, t) - i F(t) “ O€e, ie) ae = G(T) a Ol Ghee) 
t 
TE 
= F(t) + J F(t) O(T, t) f(t) dt + G(T) o(T, t) f(t) 
ap 
= F(t) - J F(t) OG) dit — G(T) O(T, 0 f(t) 
B = sj £ G23) 
with p(t) = G(T). In terms of a. (1.20) becomes 
ili 
| [- p'(c) (E(u) - £(v)) + Fu) - F(w)] do > 0 
0 
or 
il T 
| l-2e@ rp EMI ole ?@ rp E@ de2O0 Gers) 
0 
Since du is an arbitrary deviation satisfying only (1.7), it can be 
chosen such that u = v everywhere except on some arbitrary interval; as 
a consequence, the inequality in (1.24) must hold for the integrand: 
- Fv) +p) £@) > - F@) tp EW) 
Define 
H(t, u) = - F(u) +p’ £(u) (1.25) 
Then H satisfies 
H(t, v) > H(t, u) (1.26) 
13) 
