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f : [a, b] → R
[a, b] ⊂ R

b
a
f

(t)dt = f (b) − f(a)
f

(·)

Cl
f(·) (
∂f(·))
G(x) =


g(ω, x)dµ(ω),
g Ω × U U
(Ω, µ)
(P) min{f(x) | x ∈ X, g
i
(x) ≤ 0 ∀i ∈ I, h
j
(x) = 0 ∀j ∈ J},
X I J f, g
i
, h


j
X
¯x (P)
f, g
i
(i ∈ I), h
j
(j ∈ J) ¯x
λ
0
≥ 0 λ
i
≥ 0 (i ∈ I) µ
j
∈ R (j ∈ J)
0 ∈ λ
0

Cl
f(¯x) +

i∈I
λ
i

Cl
g
i
(¯x) +


j∈J
µ
j

Cl
h
j
(¯x)
λ
i
g
i
(¯x) = 0 ∀i ∈ I, ∂
Cl
X ¯x
(P) f, g
i
(i ∈ I), h
j
(j ∈ J) ¯x
λ
0
≥ 0 λ
i
≥ 0 (i ∈ I) µ
j
∈ R (j ∈ J)
0 ∈ λ
0
∂f(¯x) +


i∈I
λ
i
∂g
i
(¯x) +

j∈J
∂(µ
j
h
j
)(¯x),
∂ λ
i
g
i
(¯x) = 0 ∀i ∈ I,
(P)
G(·)
L
1
(Ω; E)
f : X →
¯
R := [−∞, +∞] X.
X X

X


X
x

, x. X
X

B
X
B
X

G: X ⇒ X

Lim sup
u→x
G(x) :=

x

∈ X




∃u
k
→ x, x

k

w

−→ x

,
x

k
∈ G(u
k
) ∀k = 1, 2, . . .

X

w

X

u
f
→ x f : X →
¯
R u

→ x Ω ⊂ X
u → x f(u) → f(x) u → x u ∈ Ω.
t → t
+
0
t ↓ t

0
t → t
0
t > t
0
t → t
0
t ≥ t
0
f x ∈ X
f x v ∈ X
f
0
(x; v) := lim sup
x

→x, t→0
+
f(x

+ tv) − f(x

)
t
.
f x

Cl
f(x) :=


ξ

∈ X

| ξ

, v  f
0
(x; v) ∀v ∈ X

.
f x v ∈ X, f

(x; v),
f

(x; v) := lim
t→0
+
f(x + tv) − f(x)
t
,
f x ∈ X.
f x v ∈ X f

(x; v)
f

(x; v) = f
0

(x; v).
ε ≥ 0, ε f x ∈ X
f(x) ∈ R


ε
f(x) :=

x

∈ X




lim inf
u→x
f(u) − f(x) − x

, u − x
u − x
≥ −ε

.
|f(x)| = ∞


ε
f(x) = ∅. ε = 0



0
f(x)

∂f(x) f x.
∂f(x) := Lim sup
u
f
−→x
ε↓0


ε
f(u)
f x
Ω ⊂ X δ(x; Ω) = 0 x ∈ Ω
δ(x; Ω) = +∞ x ∈ X\Ω
Ω x ∈ X

N(x; Ω) :=

∂δ(x; Ω) N(x; Ω) := ∂δ(x; Ω).
f x ∈ X f(x) ∈ R

F en
f(x) := {x

∈ X

| f(u) − f(x) ≥ x


, u − x ∀u ∈ X}.
f : X →
¯
R x ∈ X
f(x)  lim inf
u→x
f(u) lim inf
u→x
f(u) := sup
U∈N (x)
inf
u∈U
f(u) N (x)
X x f x
U ∈ N (x) f u ∈ U
X X
X
X
f : U → R
U ⊂ X U
(Ω, A, µ) σ− G : Ω ⇒ R
n
Ω R
n
G
G
−1
(W ) := {ω ∈ Ω | G(ω) ∩ W = ∅} ∈ A W ⊂ R
n

G k(·) ∈ L
1
(Ω)
G(ω) ⊂ k(ω)B
R
n
Ω L
1
(Ω)
Ω R
G =

g ∈ L
1
(Ω; R
n
) | g(ω) ∈ G(ω) Ω

.
G Ω
G :


Gdµ :=



gdµ | g ∈ G

,



gdµ =



g
1
dµ, ,


g
n


g = (g
1
, , g
n
).
X (X, A, µ)
A σ X.
f : U → R U ⊂ X Ω ⊂ U
µ(Ω) < ∞.



Cl
f(x)dµ(x) = ∂
Cl

F (0)
=

x

∈ X

| x

, v 


f
0
(x; v)dµ(x) ∀ v ∈ X

,
(2.1)
F (v) :=


f
0
(x; v)dµ(x).



Cl
f(x)dµ(x) (2.1)
ξ






Cl
f(x)dµ(x) ξ

∈ X

x → ξ

x
Ω X

ξ

x
∈ ∂
Cl
f(x)
u ∈ X ω → ξ

x
, u Ω ξ

, u =


ξ


x
, udµ(x).
f : X → Y X
Y.
f x
0
∈ X
D
s
f(x
0
) : X → Y
lim
x→x
0
, t→0
+
t
−1
(f(x + tv) − f(x)) = D
s
f(x
0
)(v)
v X D
s
f(x
0
)

f x
0
f

(x
0
) : X → Y
lim
x,x

x=x

−→x
0
f(x) − f(x
0
) − f

(x
0
)(x − x
0
)
x − x
0

= 0,
f x
0
f


(x
0
)
f x
0
f x
0
f

(x
0
) : X → Y
lim
x,x

x=x

−→x
0
f(x) − f(x

) − f

(x
0
)(x − x

)
x − x



= 0.
f

(x
0
) f x
0
f x
0
f
x
0
f

(x
0
) = D
s
f(x
0
). X
X
f : U → R
U R
n
Ω ⊂ U µ(Ω) < ∞.
(i)




Cl
f(x)dµ(x)
(ii) v ∈ R
n
, f

(x), v = f
0
(x; v) Ω
(iii) f Ω
(iv) f Ω.
(i) (iv)



Cl
f(x)dµ(x) =



f

(x)dµ(x)

.

b
a

f

(t)dt = f (b) − f (a)
f

(x)

Cl
f(x)
f : [a, b] → R (a, b ∈ R, a < b)
f(b) − f(a) ∈
b

a

Cl
f(x)dx (2.6)
b

a

Cl
f(x)dx =

f(b) − f(a)

f [a, b].
(2.6)
{r
k

}
k∈N
(a, b) ⊂ R
a < b k ∈ N δ
k
> 0 (r
k
− δ
k
, r
k
+ δ
k
) ⊂ (a, b) δ
k
<
2
−(k+3)
(b − a). A = ∪

k=1
(r
k
− δ
k
, r
k
+ δ
k
) P = [a, b]\A. A

R P A = ∪

j=1
(a
j
, b
j
) {(a
j
, b
j
)}
j∈N
f : [a, b] → R
f(x) =



0 x ∈ P,
(x − a
j
)
2
(x − b
j
)
2
sin
1
(b

j
− a
j
)(x − a
j
)(x − b
j
)
x ∈ (a
j
, b
j
).
f [a, b] I :=

b
a

Cl
f(t)dt
X f, g : X → R
f ∂
Cl
g(x) ⊂ ∂
Cl
f(x)
x ∈ X, α ∈ R f (x) = g(x) + α x ∈ X.
X f

Cl

g(x) ⊂ ∂
Cl
f(x) x ∈ X
f, g : R
n
→ R f

Cl
g(x) ⊂ ∂
Cl
f(x) R
n
α ∈ R
f(x) = g(x) + α x ∈ R
n
.
f : U → R
U ⊂ R
n
Ω ⊂ U µ(Ω) < ∞.


∂f(x)dµ(x) =

x

∈ R
n
| x


, v 


f
0
(x; v)dµ(x) ∀v ∈ R
n

.
f : [a, b] → R
f
0
(x; v) = max
ξ∈∂
Cl
f(x)
ξ, v =

|v| x ∈ P ∩ (a, b),

f

(x)v

x ∈ A,
v ∈ R
b

a
∂f(x)dx =


x

∈ R | x

, v  µ(P )|v| ∀v ∈ R

= [−µ(P ), µ(P )].
f : [a, b] → R (a, b ∈ R, a < b)
f(b) − f(a) ∈
b

a
∂f(x)dx
b

a
∂f(x)dx =

f(b) − f(a)

f [a, b].
F (x) =
x

a
f(t)dt, (3.1)
f [a, b] ⊂ R f
M > 0 |f(x)|  M [a, b]
L


[a, b] [a, b].
f
+
(x) = inf

M | ∃ ε > 0 f(x

)  M [x − ε, x + ε]

,
f
+
+
(x) = inf

M | ∃ ε > 0 f(x

)  M [x, x + ε]

,
f

(x) = sup

M | ∃ ε > 0 f(x

)  M [x − ε, x + ε]

,

f


(x) = sup

M | ∃ ε > 0 f(x

)  M [x − ε, x]

.
f

(x)  f


(x)  f
+
(x) f

(x)  f
+
+
(x)  f
+
(x).

f

(x), f
+

+
(x)



f


(x), f
+
(x)



f

(x), f
+
(x)

.
f ∈ L

[a, b], F (3.1)
x ∈ (a, b)
∂F (x) =

f

(x), f

+
+
(x)



f


(x), f
+
(x)

. (3.2)
∂F (x)
(3.2)
E [0, 1]
[0, 1] E [0, 1]\E
f(t) = 1 t ∈ E f(t) = 0 t ∈ [0, 1]\E
F (x) =
x

0
f(t)dt (x ∈ [0, 1]) f ∈ L

[0, 1]
f
+
(x) = f
+

+
(x) = 1 f

(x) = f


(x) = 0 x ∈ (0, 1).
∂F (x) = [0, 1] x ∈ (0, 1).
E x
0
∈ E ∩ (0, 1)
f : [0, 1] → R
f(t) =











1 t ∈ [x
0
, 1]

E,
0 t ∈ [x

0
, 1]\E,
2 t ∈ [0, x
0
)

E,
3 t ∈ [0, x
0
)\E.
F (x) =

x
0
f(t)dt x ∈ [0, 1] f ∈ L

[0, 1] f
+
(x
0
) = 3 f
+
+
(x
0
) =
1, f

(x
0

) = 0 f


(x
0
) = 2.
∂F (x
0
) =

0, 1



2, 3

.

∂F (x) = ∅.
∂F (x) =

f

(x), f
+
(x)

,
∂F (x) = ∂
Cl

F (x).
∂F (x)

∂F (x) = ∅
ϕ : I → R
I R x ∈ I

∂ϕ(x) = ∅. ∂ϕ(x) = ∂
Cl
ϕ(x).
ϕ x

0
ϕ(x) := ∂ϕ(x)∪[−∂(−ϕ)(x)] ∂ϕ(x) ⊂ ∂
0
ϕ(x) ⊂ ∂
Cl
ϕ(x) ϕ
x

∂ϕ(x) = {ϕ

(x)} = ∅
I R ϕ : I → R
∂ϕ(x) = ∂
Cl
ϕ(x) = ∂
0
ϕ(x).
L

1
(Ω; E)
(Ω, A, µ) σ−
E f : Ω×E →
¯
R A⊗B(E)−
F (u) =


f(ω, u(ω))dµ(ω) (u ∈ L
1
(Ω; E)). (3.16)
s : Ω → E
s =
m

i=1
c
i
χ
A
i
,
m ∈ N c
i
∈ E, A
i
∈ A i = 1, 2, , m Ω =
m


i=1
A
i
χ
A
(ω) = 1 ω ∈ A χ
A
(ω) = 0 ω ∈ X\A
u : Ω → E
s
k
: Ω → E
lim
k→∞
s
k
(ω) − u(ω)
E
= 0
s : Ω → E
s =
m

i=1
c
i
χ
A
i
,

m ∈ N c
i
∈ E, A
i
∈ A i = 1, 2, , m Ω =
m

i=1
A
i
c
i
= 0 µ(A
i
) = ∞. A ∈ A, s A

A
sdµ :=
m

i=1
µ(A ∩ A
i
)c
i
,
µ(A ∩ A
i
)c
i

:= 0 c
i
= 0 µ(A ∩ A
i
) = ∞
u : Ω → E
s
k
: Ω → E
lim
k→∞
s
k
(ω) − u(ω)
E
= 0
lim
k→∞


s
k
− udµ = 0.
A ∈ A u A

A
udµ := lim
k→∞

A

s
k
dµ.
L
1
(Ω; E) u : Ω → E
Ω u :=


u(ω)dµ u ∈ L
1
(Ω; E).
u ∈ L
1
(Ω; E),
I
f
(u) =



f(ω, u(ω))dµ
:= inf



v(ω)dµ | v ∈ L
1
(Ω; R), v(ω) ≥ f(ω, u(ω))


.
(3.18)
ω → f(ω, u(ω)) Ω I
f
(u) = F (u),
F (u) (3.16)
v : Ω → E
∗ ∗
e ∈ E
Ω  ω → v(ω), e L
w

(Ω; E

)

v : Ω → E

Ω  ω → v(ω) L

(Ω; R).
L
w

(Ω; E

) v
L
w


(Ω;E

)
= ess sup
ω∈Ω
v(ω),
ess sup
ω∈Ω
v(ω) = inf{α > 0 | v(ω) < α }.
L
p
(Ω, A, µ) σ− E
(i) T ∈ (L
1
(Ω; E))

v ∈ L
w

(Ω; E

)
T (u) =


v(ω), u(ω)dµ (3.19)
u ∈ L
1
(Ω; E). T  = v
L

w

(Ω;E

)
(ii) T (3.19) v ∈ L
w

(Ω; E

),
L
1
(Ω; E)
I
f
(·) : L
1
(Ω; E) →
¯
R
(3.18) x ∈ L
1
(Ω; E) f (x) ∈ L
1
(Ω; R)


ε
I

f
(x) =

x

∈ L
w

(Ω; E

) | inf
e∈E
g
ε
(ω, e, x

(ω)) ≥ 0 h.k.n.

=

x

∈ L
w

(Ω; E

) | I
f
(u) − I

f
(x) − x

, u − x
≥ −εu − x ∀u ∈ L
1
(Ω; E)

,
g
ε
(ω, e, e

) := f (ω, e) − f(ω, x(ω)) − e

, e − x(ω) + εe − x(ω), ω ∈ Ω,
e ∈ E, e

∈ E

, ε ≥ 0.
f : Ω × E →
¯
R A ⊗ B(E)−
f(u) ∈ L
1
(Ω; R) u ∈ L
1
(Ω; E) F (3.16)
∂F (x) =


∂F (x) = ∂
F en
F (x)
=

x

∈ L
w

(Ω; E

) | inf
e∈E
g
0
(ω, e, x

(ω)) ≥ 0 h.k.n.

,
g
0
(ω, e, e

) := f (ω, e) − f(ω, x(ω)) − e

, e − x(ω), ω ∈ Ω, e ∈ E, e


∈ E

x ∈ L
1
(Ω; E).
F
x
lim
k→∞
x

k
− F

(x) = 0 x

k
∈ ∂F (x
k
) lim
k→∞
x
k
= x.
F F
(P) min{F (x) | x ∈ L
1
(Ω; E)},
F (x) =



f(ω, x(ω))dµ(ω) (x ∈ L
1
(Ω; E))
x
(P)
min
e∈E
f(ω, e) = f (ω, x(ω))
f : X → R ∪ {+∞}
X
X
(i) X
(ii) f : X → R ∪ {+∞}
lim
x→∞
f(x)
x
= +∞, (4.1)

x∈X

∂f(x) = X

.
(iii) Ω ⊂ X,

x∈Ω

N(x; Ω) = X


.
X f : X → R ∪ {+∞}
f
(4.1)

x∈X

∂f(x) X

X = 
2
e
n
:= (0, , 0, 1, 0, ),
n f : X → R ∪ {+∞}
f(x) :=











1
n

+
t
2

1
n + 1

1
n

x = (1 − t)e
n
+ te
n+1
(t ∈ [0, 1) n = 1, 2, ),
+∞ x ∈ X\



n=1
[e
n
, e
n+1
)

,
[e
n
, e

n+1
) :=

(1− t)e
n
+te
n+1
| t ∈ [0, 1)

.

x∈X

∂f(x) = X

.
X Ω
X.

x∈Ω

N(x; Ω) X

.
X = 
2
e
n
:= (0, , 0, 1, 0, ) n.
Ω =



n=1
[e
n
, e
n+1
], [e
n
, e
n+1
] :=

e
n
+ t(e
n+1
− e
n
) | t ∈ [0, 1]

. Ω
X

x∈Ω

N(x; Ω) = X

.
(P

0
) min{f(x) | x ∈ X},
X f : X → R ∪ {+∞}
¯x ∈ X (P
0
) 0 ∈

∂f(¯x)
X f : X → R ∪ {+∞}
(4.1)
c ∈ X

(P
c
) min{f(x) + c, x | x ∈ X}
X f : X → R ∪ {+∞}
(4.1)
c ∈ X

(P
c
)
(P
c
)
(P
0
) c, x f(x)
(P
0

)
(P
0
)
X f : X → R ∪ {+∞}
X
(4.1) C X

c ∈ C (P
c
)
X f : X → R ∪ {+∞}
X (4.1) C
X

c ∈ C (P
c
)
F (x) =

x
a
f(t)dt, f
F (u) =


f(ω, u(ω))dµ(ω) (u ∈ L
1
(Ω; E)), (Ω, A, µ)
σ E

f : Ω × E →
¯
R A ⊗ B(E)−
X

X






L
1
(Ω, E)

×