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x
g x
→

 

 ,  

x x
x x
g x
x
→ →
− −
=
−
=>?@?A@BC
=>?@?A@BC
^0G
^0G
y =

y =


f(x)
f(x)
H$:&%I'GM,
H$:&%I'GM,
x
x
o
o
Y
Y
b
b
<
<


L
L
:_`a
:_`a
gii hn bên phi
gii hn bên phi




y = f(x)

y = f(x)
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'
x
x
→
→
x
x
0
0
!V
!V
3,
3,
x
x
n
n
24'5(
24'5(
x
x
0
0
< x
< x
n
n
<b

<b
3
3
x
x
n
n
→
→
x
x
0
0
(
(
f(x
f(x
n
n
)
)
→
→
L
L
<
<
9\V
9\V
2 +#,"789:;"


 , 
x x
f x L
+
→
=
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o
<
L:_`agii hn bên tri y = f(x)'x
→
x
0
!V
3,x
n
24'5(a<x
n
bx
0
3x
n
→
x
0
(f(x
n
)
→

L<
9\V

 , 
x x
f x L
−
→
=
x
0
b
x

x x
+
→
x
0
a
x

x x
−
→
=>?@cd
=>?@cd


'3e'

'3e'


 , 
x x
f x L
→
=
 
 ,   , 
x x x x
f x f x L
− +
→ →
= =
EV0G
3
2,@G:+$:&a:ff(x) xg



 , 
x
f x
+
→

 , 
x
f x

−
→
 
, 
 b
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f x
x x
+ ≥

=

−

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!V
 
 ,  ,    
x x
f x x
− −
→ →
= − = − = −
 
 ,  ,  
x x
f x ax a
+ +
→ →
= + = +

 
 ,   , 
  
x x
f x f x
a a
− +
→ →
=
⇔ + = − ⇔ = −
2=ff(x)x =5
 !"#'()*$+#,"# #,"
 !"#'()*$+#,"# #,"
=&
=&
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2?!V
2?!V
f(x)
f(x)
W
W
3(5
3(5
L
L
W
W
3

3
?)H,c X
 

 Y 
x x x x
x x c c
→ →
= =
!VM7

 , 
x x
f x L
→
=

 , 
x x
g x M
→
=

 Z ,  , [
x x
f x g x L M
→
+ = +

 Z ,  , [

x x
f x g x L M
→
− = −

 Z , < , [ <
x x
f x g x L M
→
=

 , 
x x
f x L
→
=

, 

, 
x x
f x L
g x M
→
=

 , 
x x
f x L
→

=




<"$=>
?+"$@A":9BC)*"#
 
 $:&a:ff(x)xg

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, 
 IV b
x x
f x
ax x

+ ≥
=

−



 


x
x x
x

→
− +
−

0G

2$:&a:ff(x) xg
UIV 
, 
IV b
x x
f x
ax x
+ ≥

=

+


 , 
x
f x
−
→

 , 
x
f x
+

→