a
0,
( )
f x
x
2
a
2
x
(
,
)
,f g D
( )
x D f x
,
( )
g x
sup{ ( )} sup{ ( )}.
x D
g x
f x
x D
( )
f x
[ ,
a
)
lim ( )
f x
x
( )
f x
[ ,
a
)
x
( , ) :
a b
f
'
( ),
x
f
'
( )
x
'
( )
f a f b
( ),
'
( )
f x
[ , ]a b
lim(
0
x
1
2
x
1
2
sin
)
x
lim
( ,
)
x y
(0,0)
3
)
3
sin(
x
2
x
y
y
2
1
xy
sin
y
) x
lim (1
(
)
,
( ,
x y
)
{ }nx
|
x
n
|
|
1
a
x
n
a
|,(0
q
1)
nx
a
y
x
sin ,x
dy
dx
u
arctan
,xz
y
u
x
,
u
y
,
u
z
u
f
(
x y
,
y z
)
,u
y
u
x y
f
(
,
)
f
(
,
)
f
(
b
a
0
[ , ]a b
b
a
( ) 0.
f x
( )
f x dx
)
2
(
b a
)
b
a
f
2
( )
.
x dx
xf
(sin )
x dx
2
0
f
(sin )
x dx
x
1
x
2 ln(1
2
x dx
)
( )
f x
[ , ]a b
( )
f x
[0,
]
( )
f x
n
1
1
x
n
1,
(
n n
n
1
1) n
x
( )
f x
arctan
x
x
0
0
( )
f x
2
x
[ 1,1]
Fourier
n
1
1
2
n
0
2
xe
dx
1 ,
2
( )
f x
(1
1
x
) x
(0,
)
f
(
,
)
1
1
n
x
f
( )
n
(
1
x
)
n
( 1) [
x
n
1
f
(
1
x
( )
n
)]
.