ر ا +,1 ا ت D & ا / /0 ا ر ت C و ت & ا+ و ت د 5 EF / /0 ا ت
G 8 ,H و ي+95 ا . ر ا 4+5 )ع - ا / ت د 5 ا EF
10 x = = = = a
( . 7L ? و ! !"ا ر ا ت 7- ا / /0 ا ي & لاود E و !ارد / /0 ا 6 $
لاود . ر
= 0 ا ب & ا 0 ا و ء O L ا ت ء F ا و ء AFPا ضر"ا و ة & ا م $
د A S ا م 5 ا +,1 ا ت D & ا
ي+ ,- ا . ر ا اد ي+ ,- ا . ر ا اد !ارد ى+<أ د $ا ت 7 ا ر ا 8 9 ا
ر ا اد س !: .
a ي+95 ا . ر ا اد . ر ا اد !ارد س !:
a
س
ت $ ا د $
10
:
@ @
--20201111 2012010
@@ @@ @@ @@
0ي+ ,- ا . ر ا اد / /0 ا ي+ ,- ا . ر ا ا +,1 ا ت 2 3 ا 4+5
ي+ ,- ا . ر ا اد !ارد / /0 ا 6 $ ف+5 ا
! !"ا . ر ا ت 7
ا ا 8 9 و ا ر ا 8 9 ا 4+5
(((( ))))
x ֏֏֏֏ln u x
ا 2أ اد & / /0 ا
(((( )))) (((( ))))
x u' x u x
֏
֏
֏
֏
س !: . ر ا اد 6 $ ف+5 ا .
a/ ى+<أ دا =4 ر ا لاو ا > ?
@A3 ا دا .
س . . ي
N
IFonction logarithme népérien
ا ا
x 1 x
֏
֏֏
ل 1 ا 6 $ A
֏]]]]
0 ,+∞+∞+∞+∞[[[[
ل 1 ا 6 $ 2أ لاود E,8 نذإ ،
]]]]
0 ,+∞+∞+∞+∞[[[[
،
=4 م 5- ة Fو 2أ اد E,8 و .
1اد ا 2"ا ا ا =ه ي+ ,- ا . ر ا
x 1 x
֏
֏
֏
ل 1 ا 6 $
֏]]]]
0 ,+∞+∞+∞+∞[[[[
=4 م 5- = ا و .
1O + D 7 O + و :
.
lnا ا > +5 $ 1 ل 1 ا =ه
ln]]]]
0 ,+∞+∞+∞+∞[[[[
.
ln 1 ====0
ا ا V D S
lnل 1 ا 6 $ ق 8
]]]]
0 ,+∞+∞+∞+∞[[[[
- و
]]]] [[[[ (((( ))))
1:
x 0 , , ln x x
∀ ∈ +∞ ′′′′ =
∀ ∈∀ ∈ +∞+∞ ==
∀ ∈ +∞ =
ا ا 6 $ 5HS اO
lnل 1 ا
]]]]
0 ,+∞+∞+∞+∞[[[[
. يأ
]]]] [[[[ :
a ,b 0 , , a b ln a ln b
∀ ∈ +∞ < ⇔ <
∀ ∈ +∞ < ⇔ <
∀ ∈ +∞ < ⇔ <
∀ ∈ +∞ < ⇔ <
.
]]]] [[[[
a ,b 0 , , ln a ln b a b
∀ ∈ +∞ = ⇔ =
∀∀ ∈∈ +∞+∞ == ⇔⇔ ==
∀ ∈ +∞ = ⇔ =
.
ln x ====0 ⇔⇔⇔⇔x ====1
و
ln x >>>>0 ⇔⇔⇔⇔x >>>>1
و
ln x <<<<0 ⇔⇔⇔⇔0 <<<<x <<<<1
.
E0 و
aل 1 ا /
b]]]]
0 ,+∞+∞+∞+∞[[[[
- ،
(((( )))) :
ln ab ====ln a++++ln b
XY
(((( )))) (((( )))) :
x 0 , F x ln kx
∀ > =
∀ > =
∀ > =
∀ > =
(((( )))) و
x 0 ,u x kx
∀ > =
∀ > =
∀ > =
∀ > =
Z F ،
k∈∈∈∈ℝℝℝℝ++++∗∗∗∗
.
-
(((( )))) (((( )))) :
x 0 , F x ln u x
∀ > =
∀ >∀ > ==
∀ > =
نذإ ل 1 ا E$ ق 8 V D S
F]]]]
0 ,+∞+∞+∞+∞[[[[
- و :
(((( )))) (((( (((( )))) )))) (((( ))))
1x 0 , F x ln u x u x
′ ′ ′ x
′ ′ ′
′ ′ ′
′ ′ ′
∀ > = × =
∀ >∀ > == ×× ==
∀ > = × =
(((( )))) نذإ
c / F x ln x c
∃ ∈ = +
∃ ∈ = +
∃ ∈ = +
∃ ∈ℝℝℝℝ = +
E أ / و
x ====1
،
ln k ====c
.
G- و
(((( ))))
ln kx ====ln x++++ln k
.
-5[و اذإ :
x ====a
و
k ====b
ن\4
(((( )))) :
ln ab ====ln a++++ln b
.
ˆbn ÿaˆbn ÿa Z
Z @@
Ùi@óïäbrÜa@óå Üa Ùi@óïäbrÜa@óå Üa
@@--20201111 201
2010@@@@@@@@ 0
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óïámŠbÈíÜÜaßaì‡Üa @ @
ârïéÜaæia@óïÝïèdnÜa@óîíäbrÜaóibïä@ãíÝÈ@bîŠíÜb
ﺌ
ŒïÐóï bî H‘î†cI
א
א
אא
ا لاو ا > +5 $ 1 د F :
f : x x
ln x
֏
֏֏
֏
(((( ))))
g : x ֏֏֏֏ x −−−−1 ln x
h : x ֏֏֏֏ ln ln x
.
=4 EF
ℝℝ ℝℝ
ا ت د 5 ا :
((((
2))))
ln 2 x ====ln x ++++1
(((( )))) (((( ))))
ln x −−−−1 −−−−ln 3 x++++1 ====0
2
x 1
ln 0
x 1
+ ++
+
=
==
=
+ + +
+
=4 EF
ℝ ℝ ℝ
ا ت & ا+ ا
ℝ:
(((( ))))
ln 3 x++++2 <<<<0
(((( )))) (((( ))))
ln x −−−−1 <<<<ln 2 x−−−−1
2
x 1
ln 0
x 1
−
−−
−
≥
≥
≥
≥
++ ++
Definition
II
/ هر,
نأ X + D / ,
(((( )))) :
i n i n
i i
i 1 i 1
ln a ln a
= =
== ==
= =
= =
= =
= =
= =
=
=
=
=
∏ ∏ ∏ ∏
∑ ∑ ∑ ∑
Z F
a1 2
و و
a...
n
و 5HS , 8 8F ادا $أ
a.
E0 و
aل 1 ا /
b]]]]
0 ,+∞+∞+∞+∞[[[[
و ، E0 /
r ℚ ℚ ℚ- ،
ℚ:
1
1
(
ln ln a
a
= −= −= −= −
2
a
(
ln ln a ln b b
==== −−−−
3
(((( ))))
r(
ln a ====r ln a
4
1
(
ln a ln a
= 2
==
=
1 ( -
1 1
:
a 0 ,0 ln 1 ln a ln a ln
a a
∀ > = = × = +
∀ > = = × = +
∀ > = = × = +
∀ > = = × = +
G- و
ln 1 ln a a
= −= −= −= −
.
2 ( -
a 1 1
:
ln ln a ln a ln ln a ln b
b b b
= × = + = −
= × = + = −
= × = + = −
= × = + = −
E0 و
a/
b∗
∗
∗
∗ + + +
ℝ+
ℝ ℝℝ
.
3 ( ن آ اذإ
r ====n∈∈∈∈ℕℕℕℕ
1 2 n
:
a ====a ====....====a ====a
6 $ EA& و :
ln an ====n ln a
ن آ اذإ
r = − ∈= − ∈= − ∈= − ∈n ℤℤℤℤ−−−−
:
r n n
n
a 0 , ln a ln 1 ln a n ln a r ln a
∀ > = a = − = − =
∀ > = = − = − =
∀ > = = − = − =
∀ > = = − = − =
ن آ اذإ
r p
= q
=
=
:
=r qr p
a ,q ln a ln a ln a p ln a
∀ > = = =
∀ > = = =
∀ > = = =
∀ > = = =
نذإ
a 0 , ln ar r ln a
∀ > =
∀ > =
∀ > =
∀ > =
آ اذإ ن
xy >>>>0
ن\4
(((( )))) :
ln xy ====ln x ++++ln y
و
ln x ln x ln y y
= −
= −
= −
= −
و
ln x2 ====2 ln x
E0 /
xل 1 ا
]]]]
0 ,+∞+∞+∞+∞[[[[
E0 و /
n∗
∗∗
ℕ∗
ℕ ℕ
- ،
ℕ:
n 1
ln x ln x
= n
=
=
.
=د 5 ا b D :
A ====ln 2 −−−− 2 ++++ln 2++++ 2
.
(((( ))))
2009(((( ))))
2009B ====ln 2 −−−−1 ++++ln 2 ++++1
=4 EF
ℝ ℝ ℝ
د 5 ا
ℝ(((( )))) :
ln − +− +− +− +x 3 ====2
& ا+ ا .c
(((( )))) :
ln − +− +− +− +x 3 ≥≥≥≥2
II (
ا ا > +5 $ 1 ل 1 ا =ه
ln]]]]
0 ,+∞+∞+∞+∞[[[[
.
1 (
د -ا ت .
xlim ln x
→+∞
→+∞→+∞
→+∞ = +∞= +∞= +∞= +∞
و
x 0
lim ln x
+ + +
→ +
→→
→ = −∞= −∞= −∞= −∞
و
x
lim ln x 0 x
→+∞
→+∞→+∞
→+∞ ====
-
x
:
x 0 x 0
lim ln x lim ln1 lim ln x
+ + x
+ +
+ +
+ + →+∞→+∞→+∞→+∞
→ →
→→ →→
→ →
= − = − = −∞
= −= − = −= − = −∞= −∞
= − = − = −∞
.
/ هر,
ˆbn ÿa ˆbn ÿa Z
Z @ @
Ùi@óïäbrÜa@óå Üa Ùi@óïäbrÜa@óå Üa
@ @
--20201111 2012010
@@ @@ @@ @@
0óibïä
ârïéÜaæia@óïÝïèdnÜa@óîíäbrÜa
@ãíÝÈ@bîŠíÜb
ﺌ ŒïÐ
óï bî H‘î†cI
א
א
אא
2 ( ا0 ا تا 1 لو0
lnا ا ل 1 ا 6 $ ق 8 V D S
ln]]]]
0 ,+∞+∞+∞+∞[[[[
- و
(((( )))) (((( ))))
1:
x 0 , ln x 0
x
∀ > ′′′′ = >
∀ >∀ > == >>
∀ > = >
+∞
+∞+∞
+∞
1
0
x
+ ++
+
+ + +
+
(((( )))) (((( ))))
ln ′′′′ x+∞
+∞+∞
+∞
0
−∞
−∞−∞
−∞
ln x
3 ( ا0 ا 5 6 7 . + ا عو 9 ا
ln-
x 0
:
lim ln x
++ ++
→
→
→
→
= −∞= −∞
= −∞= −∞
ا ا 6-&- يد $ بر 8 d ار"ا ر & نذإ .
lnxlim ln x
→+∞→+∞
→+∞→+∞ = +∞= +∞= +∞= +∞
x
و
lim ln x 0 x
→+∞→+∞→+∞
→+∞ ====
نذإ 6-&- E 2 4"ا ر & Gه 1 ا 1 $+4 E,8
lnرا 1D
+∞+∞
+∞+∞
4 ( د0 ا
eا ا ل 1 ا 6 $ 5HS اO و A
ln]]]]
0 ,+∞+∞+∞+∞[[[[
نذإ
]]]] [[[[ :
(((( )))) ]]]] [[[[
x 0 x
ln 0 , lim ln x , lim ln x ,
+ + +
+ →+∞→+∞→+∞→+∞
→→→
→
+∞ = = −∞ +∞
+∞ = = −∞ +∞
+∞ = = −∞ +∞
+∞ = = −∞ +∞
.
نأ D و
]]]] [[[[
1∈ −∞ +∞∈ −∞ +∞∈ −∞ +∞∈ −∞ +∞,
د 5 ا ن\4
ln x ====1
ل 1 ا =4 ا F و VF E,8
]]]]
0 ,+∞+∞+∞+∞[[[[
ف+& D G O + .
e- و :
ln e ====1
و
e∉∉∉∉ℚℚℚℚ
و
e ≈≈≈≈2.718
.
(((( ))))
kx 0 , k , ln e k
∀ > ∀ ∈ =
∀ > ∀ ∈ =
∀ > ∀ ∈ =
∀ > ∀ ∈ℚℚℚℚ =
و
x 0 , k , ln x k x ek
∀ > ∀ ∈ = ⇔ =
∀ > ∀ ∈ = ⇔ =
∀ > ∀ ∈ = ⇔ =
∀ > ∀ ∈ℚℚℚℚ = ⇔ =
.
x 0 , k , ln x k x ek
∀ > ∀ ∈ ≤ ⇔ ≤
∀ > ∀ ∈ ≤ ⇔ ≤
∀ > ∀ ∈ ≤ ⇔ ≤
∀ > ∀ ∈ℚℚℚℚ ≤ ⇔ ≤
5 ( ا0 ا 5 6
lnا ا 6-&- س د 5 7 A4أ = ا H8- ا =4
ln=ه
1:
y ====x−−−−1
.
ا ا 6-&- س د 5 7 A4أ = ا H8- ا =4
ln=ه
e 1:
y x
=e
=
==
.
O y
1 1
1
y=lnx
e
y ====x−−−−1
y 1x
=e
==
=
óïámŠbÈíÜÜaßaì‡Üa N óïámŠbÈíÜÜaßaì‡Üa
@ @
/ + 01
/0
= D 4+5 ا د 5 ا ا ا
f(((( )))) :
f x ====x−−−−ln x
1 ( د F
Df
تا & -$ ت 7- ا d Fأ .c
Df
.
2 ( ا ا تا+ f سردأ
f3 ( ا ا 6-&- g 7 V ا عو+L ا سردأ .
f4 ( ا ا 6-&- h9 أ .C- 5 . 5 =4
fIII (
x 0
lim x ln x 0
+ + +
→ +
→→
→ ====
و
x 1
lim ln x 1 x 1
→
→
→
→ ====
−
−
−
و
−(((( ))))
x 0
ln 1 x
lim 1
x
→
→
→
→
+ + + + ====
n x 0
n , lim x ln x 0
+ ++ +
∗∗
∗∗
→→
→→
∀ ∈ =
∀ ∈ =
∀ ∈ =
∀ ∈ℕℕℕℕ =
و
x n
n , lim ln x 0 x
∗
∗∗
∗
→+∞
→+∞
→+∞
∀ ∈ →+∞ =
∀ ∈ =
∀ ∈ =
∀ ∈ℕℕℕℕ =
x 0 x 0 x 0 t
ln 1
1 x ln t
lim x ln x lim x ln lim lim
x 1 t
x
+ + +
+ + +
+ + +
+ + + →+∞→+∞→+∞→+∞
→ → →
→→ →→ →→
→ → →
= − = − = −
= −= − = −= − = −= −
= − = − = −
.
(((( ))))
x 1
lim ln x ln 1 1 x 1
→
→
→
→
= ′′′′ =
= =
= =
= =
−−
−−
.
(((( ))))
(((( ))))
x 0
ln 1 x
lim ln 1 1
x
→
→
→
→
++ ++
= ′′′′ =
= =
= =
= =
.
(((( ))))
n n n
x 0 x 0 t 0
1 1
n , lim x ln x lim x ln x lim t ln t 0
n n
+ + +
+ + +
+ + +
+ + +
∗
∗∗
∗
→ → →
→ → →
→ → →
→ → →
∀ ∈ = = =
∀ ∈ = = =
∀ ∈ = = =
∀ ∈ℕℕℕℕ = = =
.
n
n n
x x t
ln x 1 ln x 1 ln t
n , lim lim lim 0
x n x n t
∗
∗∗
∗
→+∞ →+∞ →+∞
→+∞ →+∞ →+∞
→+∞ →+∞ →+∞
→+∞ →+∞ →+∞
∀ ∈ = = =
∀ ∈∀ ∈ == == ==
∀ ∈ = = =
ℕ ℕ ℕ
.
ℕا ت 7- ا d Fأ :
x
lim x ln 1 1 x
→+∞→+∞
→+∞→+∞
++ ++
و
2
x 0
lim 1 ln x x
+ + +
→ +
→→
→
++ ++
و
(((( ))))
3x 0
lim x ln x
+ + +
→ +
→→
→
و
(((( ))))
3x
lim ln x x
→+∞→+∞
→+∞→+∞
.
(((( ))))
((((
2))))
xlim x ln x
→+∞
→+∞→+∞
→+∞ −−−−
و
x
lim x ln x
x 1
→+∞
→+∞
→+∞
→+∞
+ ++
+
و
2 3 x 0
lim x ln x
+ ++
→ +
→
→→
و
(((( ))))
23x
lim ln x x
→+∞
→+∞→+∞
.
→+∞د 5 ا ا +, 5
(((( ))))
un n 1≥≥≥
= D 4+5 ا
≥ n:
n 1 u ln
n + + +
+
===
=
.
1 ( أ d Fأ
u1 2
و .
uب d Fأ
n 1 n
u ++++ −−−−u
D ر i - !ا و
(((( ))))
un n 1≥
≥≥
.
≥2 ( XY
n 1 2 3 n
:
s ====u ++++u ++++u ++++... u++++
d Fأ
sn
D i - !ا .c
nnlim sn
→+∞→+∞
→+∞
.
→+∞
/ + 02
/ هر,
ˆbn ÿa ˆbn ÿa Z
Z @ @
Ùi@óïäbrÜa@óå Üa Ùi@óïäbrÜa@óå Üa
@ @
--20201111 2012010
@@ @@ @@ @@
0óibïä
ârïéÜaæia@óïÝïèdnÜa@óîíäbrÜa
@ãíÝÈ@bîŠíÜb
ﺌ ŒïÐ
óï bî H‘î†cI
א
א
אא
IV (
La dérivée logarithmique d’une fonction.
ط @
/0
ق 8 V D S اد
uل 1 ا 6 $
،
I6 $ م 5- و ا
ل 1 .
I- : ق 8 V D S
uل 1 ا 6 $
نذإ ،
I6 $ A اد
u.
Iنأ D و 6 $ م 5-
uن\4 ،
IPا jL-D kL &
uل 1 ا 6 $ ةر .
IXY
(((( )))) (((( (((( )))) )))) :
f x ====ln u x
.
l آ اذإ ل 1 ا 6 $ 5HS ,
uن\4
I:
-
(((( )))) (((( )))) :
x I , f x ln u x
∀ ∈ =
∀ ∈∀ ∈ ==
∀ ∈ =
. نأ D و V D S
u6 $ ق 8 و
I(((( )))) ]]]] [[[[
u I ⊂⊂⊂⊂ 0 ,+∞+∞+∞+∞
،
و ل 1 ا 6 $ ق 8 V D S
ln]]]]
0 ,+∞+∞+∞+∞[[[[
- و
(((( )))) (((( (((( )))) )))) (((( )))) (((( )))) :
(((( ))))
u x x I , f x ln u x u x
u x
′ ′ ′ ′′′′
′ ′ ′
′ ′ ′
′ ′ ′
∀ ∈ = × =
∀ ∈∀ ∈ == ×× ==
∀ ∈ = × =
l آ اذإ ل 1 ا 6 $ 5HS , !
uن\4
I:
-
(((( )))) (((( (((( )))) )))) :
x I , f x ln u x
∀ ∈ = −
∀ ∈ = −
∀ ∈ = −
∀ ∈ = −
. نأ D و 6 $ ق 8 V D S
uو
I(((( )))) ]]]] [[[[
u I 0 ,
− ⊂ +∞
−− ⊂⊂ +∞+∞
− ⊂ +∞
و ل 1 ا 6 $ ق 8 V D S
ln]]]]
0 ,+∞+∞+∞+∞[[[[
- و
(((( )))) (((( (((( )))) )))) (((( )))) (((( )))) :
(((( ))))
u x
x I , f x ln u x u x
u x
′ ′ ′ ′′′′
′ ′ ′
′ ′ ′
′ ′ ′
∀ ∈ = − − × =
∀ ∈∀ ∈ = −= − −− ×× ==
∀ ∈ = − − × =
l آ اذإ ق 8 V D S اد
uل 1 6 $
،
I6 $ م 5- و ا
ل 1 ا ا ن\4 ،
I(((( ))))
(((( ))))
x ֏֏֏֏ ln u x
ق 8 V D S 6 $
6 $ 8 9 ا 7 اد و
Iا ا =ه
I(((( )))) :
(((( ))))
u x
x u x
֏ ′′′′
֏֏
.
֏د F
(((( ))))
f ′′′′ x
E0 ل 1 ا /
x& ا =4
Iا ت :
1 (
(((( )))) ((((
2))))
f x ====ln x ++++x++++1
و
]]]] [[[[
I = −∞ +∞= −∞ +∞= −∞ +∞= −∞ +∞,
.
2 (
(((( ))))
f x ====ln 1−−−−ln x
و
]]]] [[[[
I ==== e ,+∞+∞+∞+∞
.
/0 ل 1 6 $ ق 8 V D S اد
u،
I6 $ م 5- و ا
ل 1 .
Iا ا
(((( )))) :
(((( ))))
u x
x u x
֏ ′′′′
֏
֏
ا ر ا 8 9 ا 6
֏ل 1 ا 6 $
u I/0 6 $ ق 8 V D S اد
uل 1 6 $ م 5- و ،
Iا ل 1 .
Iلاو ا ا 2"ا
(((( )))) :
(((( ))))
u x
x u x
֏ ′′′′
֏֏
ل 1 ا 6 $
֏لاو ا =ه
I(((( )))) :
(((( ))))
x ֏֏֏֏ ln u x ++++c
((((
c∈∈∈∈ℝℝℝℝ)))) Z F
و ا ا 2"ا لا
x 1
2 x ++++1
֏
֏
֏
ل 1 ا 6 $
֏ , 12
−∞ −−∞ −−∞ −
−∞ −
لاو ا =ه
1
:
x ln 2 x 1 c
2 ++++ ++++
֏
֏֏
،
֏((((
c∈∈∈∈ℝℝℝℝ))))
ا 2"ا لاو ا
x ֏֏֏֏tan x
ل 1 ا 6 $
2 2, π ππ π π ππ π
−
−−
−
لاو ا =ه
x ֏֏֏֏ −−−−ln cos x ++++c
((((
c∈∈∈∈ℝℝℝℝ)))) ، .
óïámŠbÈíÜÜaßaì‡Üa N óïámŠbÈíÜÜaßaì‡Üa
@ @
د 5 ا ا ا +, 5 4+5 ا
fل 1 ا 6 $
]]]]
2 ,+∞+∞+∞+∞[[[[
= D
(((( )))) :
x2
f x ====4 x
−−
−−
.
1 ( 8 8& ا دا $"ا د F و
aو
bZ &D
c]]]] [[[[ (((( ))))
b c:
x 2 , , f x a
2 x 2 x
∀ ∈ +∞ = + +
∀ ∈ +∞ = + +
∀ ∈ +∞ = + +
∀ ∈ +∞ = + +
− +
− +
− +
− +
2 ( ا 2"ا لاو ا i - !ا ل 1 ا 6 $
f]]]]
2 ,+∞+∞+∞+∞[[[[
.
ا 2"ا لاو ا د F
$
fل 1 ا 6 ا ت & ا =4
I:
1 (
(((( ))))
3 4
f x x
x 1
==
== ++ ++
و
]]]] [[[[
I = −∞ +∞= −∞ +∞= −∞ +∞= −∞ +∞,
.
2 (
(((( ))))
1f x ==== x ln x
و
]]]] [[[[
I ==== 0 ,1
/0 =8 8& ا + f د 5 ا ا ا
f= D 4+5 ا x
(((( )))) (((( )))) :
f x ====x ++++ln ln x
.
1 ( ا ا > +5 O F نأ l,cأ ه
f]]]] [[[[
Df ==== 1 ,+∞+∞+∞+∞
.
2 ( d Fأ
(((( ))))
f ′′′′ x
تا+ f i - !ا .c ا ا
.
f3 ( ا ا 6-&- g 7 V ا عو+L ا سردأ .
f4 ( ا ا 6-&- h9 أ .C- 5 . 5 =4
f/ د 5 ا / ا ا +, 5 و
u=8 8& ا + f
f= D / 4+5 ا
x:
(((( ))))
2u x ====x −−−−2 x ++++3
و
(((( )))) ((((
2))))
f x ====ln x −−−−2 x ++++3
.
1 ( أ نأ / D
(((( )))) :
x ,u x 0
∀ ∈ >
∀ ∈ >
∀ ∈ >
∀ ∈ℝℝℝℝ >
نأ i - !ا و
]]]] [[[[ :
Df = −∞ +∞= −∞ +∞= −∞ +∞= −∞ +∞,
ب d Fأ
(((( )))) :
u 1++++ 2
(((( )))) و
u 1−−−− 2
.
2 ( / 7- ا d Fأ
(((( )))) :
xlim f x
→+∞→+∞
→+∞→+∞
(((( )))) و
xlim f x
→−∞→−∞→−∞
.
→−∞3 ( d Fأ
) x ( f′′′′
ا ا تا+ f سردأ .c .
f4 ( د 5 ا وذ . 8 ا نأ / D
"
x ====1
"
6-&- Ec ر &
ا ا .
f5 ( أ l,cأ
ا يو ا
(((( ))))
2:
*
2 3
ln x ln 1
f ( x ) x x
x , 2
x x x
− +
− +
− +
− +
∀ ∈ = +
∀ ∈ = +
∀ ∈ = +
∀ ∈ℝℝℝℝ = +
.
ب ا ا 6-&- / g 7 V ا / $+L ا سردأ .
f6 ( أ ا ا 6-&- نأ / D ,8
f7- Eآ =cا Fإ د F .c ف H5 ا = H8 E .
ب ا ا 6-&- .!رأ .C- 5 . 5 =4
f.
7 ( /0 ا ا ر AS
gل 1 ا 6 $
f[[[[ [[[[
I ==== 1 ,+∞+∞+∞+∞
.
أ ا ا نأ / D ل 1 ا / ED 8
gل 1 &
Iq & .
J.
ب + ,5 د F
(((( ))))
g−−−−1 x
D E0
x/
x.
J) r<
:
ln 2 ≈≈≈≈0.7
و
ln 3 ≈≈≈≈1.1
(
/ + 03
/ + 04
/ + 05
/ +
06
ˆbn ÿa ˆbn ÿa Z
Z @ @
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@ @
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אא óïámŠbÈíÜÜaßaì‡Üa N
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V ( )
aa >>>>0
و
a ≠≠≠≠1
( :
a
1 (
/0 د 5 L 3 و 5HS , 8 8F اد $
a1
س !: . ر ا اد
O + D 7 O + = ا د 5 ا ا ا =ه
a Logaا و 6 $ 4+5
]]]]
0 ,+∞+∞+∞+∞[[[[
= D
(((( )))) :
a
Log x ln x
= ln a
=
=
=
2 (
(((( ))))
Loga 1 ====0
(((( ))))
Loga a ====1
(((( ))))
a
Log e 1
=ln a
==
=
(((( ))))
e
x 0 , Log x ln x ln x
∀ > = ln e =
∀ > = =
∀ > = =
∀ > = =
- و
e
G
ln====Log
.
E0 و
xل 1 ا /
y]]]]
0 ,+∞+∞+∞+∞[[[[
E0 و ، /
rℚℚℚ
- ،
ℚ:
1
(((( )))) (((( )))) (((( )))) (
a a a
Log xy ====Log x ++++Log y
2
a a
(
Log 1 Log x
x
= −
= −= −
= −
3
(((( )))) (((( )))) (
a a a
Log x Log x Log y
y
= −
== −−
= −
4
(
(((( ))))
ra a
Log x ====rLog x
= b D :
(((( ))))
2 2
A Log 1 Log 10
5
= +
= +
= +
= +
(((( ))))
51 3
B ====Log 3
3
a (
ا ا
Loga
ل 1 ا 6 $ ق 8 V D S
]]]]
0 ,+∞+∞+∞+∞[[[[
- و
((((
a)))) (((( )))) :
ln x 1
x 0 , Log x
ln a x ln a
′′′′
∀ > ′′′′ = =
∀ > = =
∀ > = =
∀ > = =
/ ا / و 1 ا i- G- و :
F
a>>>>1
+∞
+∞+∞
+∞
a
1
0
x
+++
+ +++
+ +++
+
((((
Loga))))
′′′′(((( ))))
x+∞
+∞+∞
+∞
1
0
−∞−∞
−∞−∞
(((( ))))
Loga x
F
0 <<<<a <<<<1
+∞
+∞
+∞
+∞
1
a
0
x
++ ++
++ ++
++ ++
((((
Loga))))
′′′′(((( ))))
x+∞
+∞
+∞
+∞
0
1
−∞−∞
−∞−∞
(((( ))))
Loga x
.
Fonction logarithme de base