lim
x→e
ln x−1
x−e= lim
x→e
ln x−ln e
x−e=1
e
lim
x→0
ex2−1
x= lim
x→0
ex2−1
x2∗x= 0 lim
X→0
eX−1
X= 1
lim
x→0
ln(1 + 5x)
x= lim
x→0
ln(1 + 5x)
5x∗5 = 5 lim
X→0
ln(1 + X)
X= 1
lim
x→(1
e)+
ln x−2
ln x+ 1 =−∞ lim
x→(1
e)+(ln x−2) = −3 lim
x→(1
e)+(ln x+ 1) = 0+
lim
x→+∞(x−ln x) = lim
x→+∞
x(1 −ln x
x) = +∞lim
x→+∞
ln x
x= 0
lim
x→+∞
e2x
ex+x2= lim
x→+∞
1
e−x+x2e−2x= +∞lim
x→+∞
x2e−2x= 0+
x∈IR, (ex2+5x)0= (2x+ 5)ex2+5x
x∈IR, (e−2e−5x)0= (−2e−5x)0e−2e−5x= 10e−5xe−2e−5x= 10e−2e−5x−5x
x > ln 3,(ln(ex−3))0=ex
ex−3
x∈]− ∞,−1[∪]1,+∞[,(ln(x−1
x+ 1))0=
(x+1)−(x−1)
(x+1)2
x−1
x+1
=2
(x−1)(x+ 1)
x∈IR∗
+,(xln x−x)0= (ln x+ 1) −1 = ln xln
x∈IR∗
+,(xx)0= (exln x)0= (xln x)0exln x= (ln x+ 1)xx
x∈[−2
3,+∞[,((3x+ 2)√3x+ 2)0= ((3x+ 2)3
2)0=3
2∗3∗(3x+ 2)1
2=9
2√3x+ 2
x∈IR, ((x2+ 1)0,2)0= 0.2∗2x∗(x2+ 1)−0,8=0.4x
(x2+ 1)0,8
f
f(x) = ex−1
ex+ 1
f
f x ex+ 1 6= 0 x ex+ 1 >1Df=IR
x∈ Df−x∈ Dff(−x) = e−x−1
e−x+1 =1−ex
1+ex=−f(x)
f f IR−IR+
limx→−∞ ex= 0 lim−∞ f=−1
lim+∞f= 1
f IR ∀x∈IR, f0(x) = ex(ex+1)−ex(ex−1)
(ex+1)2=2ex
(ex+1)2>0f
IR
flim−∞ f=−1 lim+∞f= 1 f(0) = 0