C-UON
TRAN BA HA
AM NANG
LUYI^THI
DAI HOC
IIGUYEN HOM
*
*
THU VIENTINHBINHTHUAfO
mk nXr ikn i « i nc wfc cu M Mi
Cty TNHH MTV D VVH Khang Vi^t
LOI N O I £>AU
Phanli
I
N G U Y E N H A M - T I C H P H A N V A \SNG
Chuong
1:
2. Tinh chat co ban:
+ Neu F(x) la mot nguyen ham cua f(x) tren D thi F(x) + C cixng la nguyen
ham ciia f(x) tren D (C la hang so)
+ Neu F(x) va G(x) la cac nguyen ham cua ham so f(x) tren D thi ton tai hSng
soCdeG(x) = F(x) + C
+ Ky hieu: jf(x)dx = F(x) + C ( l a h o nguyen ham ciia ham so f(x))
+ Neu f(x) va g(x) co nguyen ham tren D thi:
l[f(x) + g(x)dx = Jf(x)dx + l(x)dx
jkf(x)dx = kjf(x)dx, ke R
Trdn Bd Ha
Gido vien THPT Chuyen Le Quy Don - Dd Ndng
Tu nghiep tgi: lustitut de Recherche
Pour L 'enseignement des Mathe 'matiques
Paris-France
Nha sach Khang Viet xin tran trong giai thieu tai Quy doc gia va xin
long nghe moi y kien dong gop, decuon sdch ngay cang hay han, botch han.
Thuxinguive:
Cty T N H H Mpt Thanh Vien - Dich vu Van hoa Khang Vi?t.
71, Dinh Tien Hoang, P. Dakao, Quan 1, TP. H C M
Tel: (08) 39115694 - 39111969 - 39111968 - 39105797 - Fax: (08) 39110880
Hoac Email:
+ Neu Jf(x)dx = F(x) + C thi Jf(ax + b)dx = - F(ax + b) + C
a
+ Moi ham so lien tuc tren D deu co nguyen ham trenD.
Y
F '(X) =
F'(x)=-2
4-x
csmx + dcosx
F(x) la nguyen ham cua f(x) <=> F '(x) = f(x), Vx
o (Ac - Bd)sinx + (Ad + Bc)cosx = asinx + bcosx, Vx
Ac-Bd = a
^
,
ac + bd „
bc-ad
Giai he ta co: A = — — - y ; B = — —
A d + Bc = b
c-+d^
c^+d'
{
Vay ho nguyen ham ciia f(x) la:
ac + bd
be - ad ,
^
^
F(x) =
r- + —
nil
ihiiiy, liivci]
- Xyjiv'ii
lu'iiii - Tirh
f)ficiii - Soptiijc - Trcin Bci Ha
Giai
F(x) la nguyen ham ciia f(x) <=> F '(x) = f(x), Vx e (—; oo)
xe^-Ce"-!)
5a = 20
Khi
x^
0 thi F
Khi
X =
0 thi F '(x) = I ' m
0
Giai
Theo dinh nghia ta c6: F '(x) = f(x), Vx ^ 1
-(2xln|x| + f r )
1-x"
« f(x) = x.1-x
x+1
n.x"-'-(n + l ) x " + l
1-x
> dpcm.
(x-1)'
= 2xln(l + x) - 2xln I x | + (x - 1) - x
Vay F '(x) = xln
1+x
Bai 12: Cho f(x) = xln - va g(x) = x^ln 4
4
-1.
Xet G(x) = F(x) + X => G '(x) = F '(x) + 1 = f(x) nen G(x) la nguyen ham ciia f(x;
16
c) Ta c6: sin'>2x + cos"2x = (sin^2x + cos22x)(sin^2x + cos''2x - sin22xcos22x)
= l((sin22x + cos22x)2- 3sin22xcos22x) = 1 - - sin24x
4
'l-cos8x'
.1-2
4
-1
x + — + 2.x2.x3 dx
12 '
— + 3.x' + — x * + C =
2
7
2
dx
2
Bai 4: Tim ho nguyen ham ciia cac ham so':
a)
1 -cos4x
(sin^ X + cos'' x ) " d x =
.
-7
r
-d(x + l) +
b) cos'x.sinSx
Giai
3
(x + l)-
a) Ta c6: cosxcos2xsin4x = ^ [cos3x + cosx]sin4x
Ai»
Bai 8: Tinh I =
= — [sin4x cos3x + sin4x.cosx] = - [sin7x + sinx + sinSx + sin3x]
Do do: fees X cos 2x sin 4xdx = — f(sin 7x + sin 5x + sin 3x + sin x)dx
J
4
4 J
' —cos7x+—cos5x+ —cos3x+
4^ 7
5
3
b) Ta c6: sinSx.cos-'x = sinSx .cosx
2cot^2x
sin"2x
sin"2x
sin"2x
Do do: I = 32Icot2x + - cot^2x + - cot^2x] + C
3
5
= — (sin9x + sin7x) + — sin8xcos3x + — sinSx.cosx
4
4
4
71
Bai 9: Tinh
cos 2x + i^ .cos 3x + - dx
3J
4
= ^ (sin9x + sin7x) + ^ (sin! 1 x + sin5x) + ^ (sin9x + sin7x)
Giai
1
A
B
A + B(x + 1) Bx + A + B
- +
^=
'
=
^
(x + 1)'
(x + 1)(x + 1)'
(x + 1)'
Dong nha't ta c6: B = 3, A = -2
10
f - 4 x ' + 9x + l
B
9-4x"
cos 5x + —
I2J
+ cos
X
1
Bai 7:
3x +1
1
Ta c6: cos 2x + — cos 3x + 4;
3
Giai
1=
4x'-9x'-l
4x"-9
xdx
dx =
1
—
6-'Ux-3
x -
1
( 2 x - 3 ) ( 2 x + 3)J
2x + 3 j
X
X =
(x-1)^
n(n + l)
b) fn+i(x) = 1 + 2.x + 3x2 +
x-1
(tong cua cap so'nhan)
+
A p d u n g p h u o n g phap t i m ho nguyen ham de t i m F(x) + C
+
D u a vao dieu k i ^ n cho t r u o c de xac d j n h hang so'C.
Bai 1: T i m n g u y e n h a m F(x) cua h a m so'f(x) = cot^x biet F( — ) = 0
4
Giai
^1
f c o t ^ x d x = f ( l + c o t ^ x - l ) d x = f ( — \x + C
J
Hay
C =1 +
; Vay: F(x) = -cotx - x + 1 + ^
Bai 2: C h o f(x) = sin^x(1 + tanx) + c o s \ ( l + cotx)
T i m n g u y e n h a m F(x) cua f(x) biet F( — ) = 1
4
Giai
Rut gon f(x) ta c6: f(x) = sinx + cosx
Jf(x)dx = sinx - cosx + C => F(x) = sinx - cosx + C
F(-) =l < : ^ s i n - - c o s - + C =1 « C = 1
4
4
4
Vay F(x) = sinx - cosx + 1
Bai 3: C h o f(x) =
?
. T i m nguyen h a m F(x) biet F( - ) = 0
l + cos2x
3
Giai
f(x) =
2
V§yF(x)=itanx
12
13
Cam
iwn}^
luy('n
thi DH
Bai 4: C h o f(x) =
•1.
- Nguyen
ham - Ticli plum
- So phi'rc
- Trdn
Bd
C = c o t - =
6
6
X
^
1
F{-)=
+C = — c^C
4
8
4
4
1
1
D o d o F(x) = — (3x - — sin2x) -
•
Vay F(x) = - c o t x + ^/3
F(x)= ^ ( 3 x - ^ s i n 2 x ) + C
1
••
D o d o F(x) = tanx In(sinx) + ^ Xnyjl
'r>'> f>Tii^t^f'-^
Giai
Cty
Ha
^371
=
8
371
—
Bai 6:
a) C h i i n g m i n h F(x) = tanx In(sinx) - x la mot n g u y e n h a m cua:
-1
Bai 8: C h o bie't F(x) =
la nguyen ham cua f(x). T u n f(x - 1)
x +1
Giai
f(x) = F ( x ) =
4
4
4
4
15
Cdm nang luyeti ihi DH - Nguyen ham - Tich phciii - So phi'rc - Trdn Ba
PHl/ONG PHAP T I M NGUYEN H A M
Chuyendel:
Van
Cly TNHH AfTV D VVH Khang Vi(H
Ha
de 1 : T I M H Q N G U Y E N H A M B A N G
3 1 [71
P H U O N G PHAP D O I BIEN SO
Phuong phap: Co the doi bien so theo hai each sau:
.
^ s /(sin X -
•'vu •
A
^^=jTr"
1
COS X
COS X
cosx
cos'x
l-sin'x
Vay
r.Datx =
Ta c6: dx = 6tMt, do do:
f sinx + cosx
hi•"Vsinx-cosx
dt
b)f(x)=^
sm X
j x V ' x - - l d x = ^ jyf^du = - A / 7 + C = \^{\'-\f
11--4
a"
= a(l + tan2t)dt
cost
a) Dat u = x^ - 1 => du = 2xdx, do do:
-u^
1 / 1
2 J 1+ u
1+u
du = —In
+ C
1- u
2
1-u
1 -i-sinx
= -ln
+ C
cosx
2
-sinx
X
1
— ^ — ( 1 -i-cot- x)dx
sin- X
Dat u = cotx => du =
+ C
f du
''>i-'• •
'•••tdu =
-I
du
J=
b) Dat X = asint-—
3^-h2''
.
a)
fcos X ,
f(l - s i n - x )
< I
dx = \
^cosxdx =
sin X
sin X
V sin
1
1
b) f
'
dx = f (sin x + COS x ) "
• ' l + sin2x
J^'^i
'
, do do
sin
Va" -
u' = 2(x - 1 )
(x - l ) e ' ' ' - ' " M x = i je-u'dx - i Je-du
Dat u = (1 + xe") => du = (x + l)e''dx, do do:
1
—cot
2
+ C
-dx
xO + xe")
rf
d(sin x ) :-tk
4J
x +1
du
X
X
sin^x + C
< " " ^ " -dx
xe^(l + xe^)
r
X"
u-Hl
= In sinx |
cos t - 1
f (x)dx - V a ' -
2(ln3-ln2)
u-1
Giai
1,
du = a u + - l n
+ C
u +1
2
u+1
-In
a) f(x) = —
sinx
u-du
(
iiiir.yi
/in cii llii
• ;/ - / A /; plum
/'// - A i v / i iv;
- So
phllV
OyTNHH
BaHa
V a n de 2: T I M H Q N G U Y E N H A M B A N G P H l J O N G P H A P N G U Y E N
HAM Tl/NG PHAN
Lai dat u = Inx => du =
dx
Phucmg phap: Gia six u(x), v(x) la cac ham so c6 dao ham lien tuc khi do ta c6:
Ju(x)v'(x)dx = u(x)v(x) hay
du = 2(x + l)dx
•
dx
Xet A :
1
v= —
(x + l ) s i n 2 x d x . Dat u = x + 1 =>du = dx
dv = sinZxdx => V = — cos2x
2
dx = - - l n ^ x + 2 t e d x
Y
X"
X
1
a) D|itu = x + 1 =:.du = dx
+ Tong quat: Phan tich f(x)dx thanh u va dv sao cho: t u dv suy ra duq^c v va
fflnx^
=>
Giai
V=
a) f(x) = (X + l)sin2x
P(x) Inxdx: Dat u = Inx, dv = P(x)dx
dx
—
X"
dx
Bai 2: Tim ho nguyen ham ciia cac ham so:
+
u = In X => du =
dv=
Vay: | ( x ' + l ) e ^ " d x =
x +1
C
e
+ - C
+C
cos" X
= tan X
f d ( c o s x ) = xtanx + In | cosx I + C
cosx
a) f(x) = e"2^cos3x
b) f(x) = sin(lnx)
Giai
d u = -2e-2^dx
- ifs.:c
e~"'cos3xdx = — e - \ s i n 3 x +
J
v = -cos xdx
V
Bai 6: T i m ho n g u y e n h a m cua cac h a m so':
Dod6:I=
D o d o : Jte'dl = te' - je'dt = ( I - l)c' + C = (Vx - Oc"^ + C
22
dx
1 > ' ?'/ ^ /K^*
d v = cosSxdx => V = — sin3x
du = dt
> du = c ' d x
-V= -cotx
=> du = dx
Dat u = t
=>du=dx
A = - x c o t x + In I sinx I + C
d v = e^'dx => V = — e^^
— e dx = —e
2J
T
dv =
.< :. - ci
., .
rd(sin
•d(sin X
x)
Do d o : A = - Xcot x +
J ssin
in X
X
Xet J = Jxe-''dx. D a t u = x=>du = dx
= —e
2
,
v = - ~ c o s S x
d u = — sin(ln x)dx
X
d v = dx
B = xcos(lnx)+
^
Vx-' + k
Dat u = X => d u = dx
+ x^
- je^dx = (x - 1
-
d u = —
Giai
a ) D a t u = ln(x + V l + x- ) = ^ d u =
dv
1=
fxln(x + V l + X - ) ,
n
7,
r
7
,
^ x = Vl + x M n X + Vi + X- Vi + - '
u = Vx" + k
dv = dx
24
Do d o :
dx=> V = V l + x"
V =
dx
-x +C
=x>du=
^
dx
Vx-'+k
V = X
r.
dx
X in xdx — i n x - •-dx = — I n x - — + C
2
2
2
Chuyen de3: N G U Y E N H A M CUA
Van
Trdn Ba Ha
CIV TNIIIIMTVDVVHKhang
C A C H A M S O CCf B A N
de 1: N G U Y E N H A M C U A C A C H A M SO
H U U
gai 2: T i ' " ho nguyen ham cua cac ham so'
^
a) f(x) = 3
TI
Phuang phap: De t'lm ho nguyen ham ciia cac ham so'dang
P(x)
,
i ;
3x- + 1
_ .—
7
l - k ' ( x + a )k-l
'
'>
+c
+ Chu y phirong phap dong nhat da thiic khi phan tich
b)
Bai 1: Tim hp nguyen ham cua
1
u\/ \x + 3
X" + 2 x - 3
a)f(x)=x'-3x + 2
Dodo: f — ^ — ^ '
dx = - - l n x - l + — l n x + 2 + — l n x - 3 + C
•"x - 2 x - - 5 x + 6
3
15
5
3x + l
A ^
B
^ C _ A(x-l)(x-2) + B(x-2) + C(x-l)(x-l)-(x-2)
B
A
f dx
J
X -
2
= ln
x-2
Vay
3x + l
(x-l)-(x-2)
dx = - 7 1 n x - l +
+ 71n
x-l
B =l
-2A-B =I
(x-l)-
x-2
+ 71nx-2 +C
+C
M i 3 : Tim ho nguyen ham ciia cac ham so:
+ C
7
a)f(x) =
B
4
B= ^
4
X"
(x-l)'
x'-7x-+14x-8
Giai
X - l+ x + 3
r 4x-3
,
7 r dx
9 r dx
• •
Viet
(X-l)'
r
x'-l +l
x +1
(x-l)'
(x-l)'
+ -
(x-l)'
(x-l)'
(x-l)'
(x-l)'
x^
J r — : 5 - d x = f(x-1)-'dx + 2 f ( x - l ) - ' d x + f(x-1)^dx
( x --l1)
•>-2
1 J „
• +
•
x - 2 ' x - 4
Dat u = X + 1 => d u = dx
- A ( x - 2 ) ( x - 4 ) + B ( x - l ) ( x - 4) + C ( x - l ) ( x - 2)
dv =
(x-l)(x-2)(x-4)
dx
(2x-l)'
D o do: k =
D u n g he so bat d j n h (gia trj dac biet)
x = l r : > A = 3 ; x = 2 r : ^ B = - 7 ; x = 4=>]< = 5
f
= 31n
x"+2x + 6
-dx = 3
•7x- + l 4 x - 8
dx
x ' - g x ' + ie
A
A
(x-1)'
(x-l)'
( x - 2 ) . 2 . ( x + 2)-
(x-2)-
D
+
x-2
(x + 2)-
x+2
+•
Vay:
,
xdx
(x'+3)-'-4
_ I r dt
1 ff
•' x' x' '' +' +6 6x x- +
- +5 5 " 22 - Jt
't'-4
Bai 6: Tinh k =
28
j
x + 1
(2x-l)'
dx
X - I
3
3
1
^ 3x + 7
dx = 2 f ^ + p ^ = 21n|x
\1 + In x + 3 + C
Jx + l
•'x + 3
'
x" + 4 x + 3
Phuong phap:
Ho nguyen Mm dang: [R
R
D a t t = x2 + 3 =:> d t = 2xdx, d o d o :
f
r-+-
Yande2: N G U Y E N H A M M Q T S O H A M V 6 T I
Giai
I
C
(X-l)-
<=> Q _ 3, do d o : M =
3
•' X -
D o d o : Bx--' - 16x + 1 = A ( x + If + B(x - 2)(x + 2)^ + C(x - If + D(x - 2)2(x + 2)
Thay Ian l u o t cac gia t r j : x = 2, x = - 2 va x = 0, x = 1
4(2x-l)
A =3
Bai 8: T i n h N = f ,
C
2(2x-l)-'
D o n g nhat ta c6: x^ + x + 1 = Cx^ + (B - 2C)x + A - B + C
=^k= -
B
B
x- + X + 1
x ' ' - 8 x - + 1 6 ~ ' ^ ^ ( x - 2 ) - ( x + 2)^
8x^-16x + l
1
0 : dat xt ± - / c = V a x ' + bx + c
= 3[Y+
Neu ax^ + bx + c c6 nghiem xi, X2, dat Vax' + bx + c = t(x - xi)
vrri+Vx+T
Giai
^
ax2
+ bx + c = a
A
X +—
Dat X + 1 = f' => dx = 6^dt, ta c6:
^ r(t'
=
+ Dt'dt
5
i+i
C = 6 (t- - t + l ) ( t * - t ^ ) d t = 6 ( t ' - t ^ + f - r + f - t ^ ) d t
or.
'R,{u,>/u--a-)dii:ctatu=
C= 6
cost
+ C, vol t = 'Vx + 1
9
8
7
6
5
4
t2 + x 2 - 2 t x =
Dat X - a = t
•
•r.-n •••KV
+ 2x + 3
t=-3
^
1 t-+2t + 3
dt
=> dx = —
(t
+
=8
t-i
t+
= l n t + l + C = ln x + i + V x ' + 2x +3 + C
dt
dx
S i i S : Tinh E =
• tdt
Vx^ +6x + 8
= 4ln!t- + l!-8arctant + C
Giii
t- + l
dx
Bai 2: Tinh B =
^ ^ t t - x = V x ' + 6 x + 8=>x =
2(t + 3)
E=
f - ^ = lnlt + 3 + C = lni x + 3 + -\/x- +6\ 8
Jt + 3
'
(lyTNHHMTV
phitt»ng phap
a. Dgng R(sinx, cosx).
Giai
dx=
X= -^^-^
2(t-2)
0-2)^+4
r-8
F=
X
= 1 - 2(t-2)
(t-2)-^
d e d u a ve
X
,
I
b)f(x) =
cosx
1+sinx
sin x(l+cosx)
Giai
+ Vx' -4x + 8
. , f dx
rcosxdx
fcosxdx
I= I
= I
5— =
r-r
""cosx "'cos^x
•'l-sinD$t u = sinx ==> du = cosxdx, ta co:
6 : I1= - J ^ .
D a t t + x = V x ^ + 2x + 2 = > x = - — ^
2(1-t)
J r(l-l)
= - l n l - t — + C, v 6 i t = V x - + 2 x + 2 - x
t
^dt
cos
2t
1+
t'-2t +2
fl^-^-dt:=
—dx = ——dx=?dx=
•
2t
l - t '
l a co smx = — ~ , cosx = - — — , suy ra
l + t^
l +t
Giai
r G-
- . cosx
l + t-
Itr^ng giac c6 lien quan dao ham roi diing doi bien so'de tinh hoac dung
dx
j
(x + l)Vx^ +2x + 2
Bai 7: Tinh G =
2t
.
b. D^ng bac cao theo sinx, cosx, tanx: Bien doi ve d^ng chiira hai nhom ham
8
16
dt
t -2^(t-27
4J
,
D|[t t = tan—, ap dung sinx =
2
X
a) Dat t = tan — => dx =
-di
2
1 +
dx
Do do:
r dt
+t
1 + sin x + cosx
1=
1 + t2t
1-t1+ - y +
,
1+t1 + t-
M
-dt
2 + 2t
Giai
a) f(x) =
y-y + C
— cos''x - — cos''x + C
7
5
2t'
cosx
X
Dat t = cosx => dt =-sinxdx. Do do:
4J
L_2__L
t
— ^
sin
a) Jcos^ xsin' xdx = Jcos^ x(l - cos" x).sin xdx
I = - Jt'(l-t')dt = -J(t'-t')dt= -
r
4
a) f(x) = cos''xsin^x
_L±tL^=f(i±i;idx =
^dt ; sinx=
2
1 + tdt
dx
sin X
-dx =
I = In I sinx I - sin^x + — sin^x + C
=:|nl + t + C = lnl + t a n - + C
X
cos'x^
X
1
sin-
- + cot' \
sin'
X
cot^x^
X
sin" X
2
1
1 3
— + cot^ X . , + cot' x . — + — — +1
sin X
sin" X
sin x sin x
Cam nang lny^n thi DH - Nguyen ham - Tich p/ic'in - So phiic — Tran Bd Ha
Vai:
sin'* X
2
1
r3x
x
i
f3x
x^
1
— sin f x x^ - s i n
sin — + — - s i n
—+
—
—
—
—
12 —3)
4
4
1/
I2
3)
I2 3 ;
I 2
3)
b) f(x) = cos*x
ri + cos2xV ^_i_r,1 + 2cos2x + COS" 2x
cos''x •
In
/'l+cos2x
l + 2cos2x +
l+cos4x
. 5x
sin
6
. X
. llx
. 7x
sin — sm
+ sin —
6
6
6
-6
5x ^
x 6
llx 6
7x
1" D o d o : fsinxsin—sin—dx = —
—cos — + 6 ct)s — + — cos
cos—
6 11
6
C. B A I T A P T O N G H Q P V E N G U Y E N H A M
1. B A I T A P TV" L U A N
I5L
Bai 1: Cho f(x) = x V 3 - x
. T i m a, b, c de ham so F(x) = (ax^ + bx + c ) V 3 - X
la
m o t n g u y e n ham cua f(x).
"3V3
Vay F(x) =
+ 1'
3N/3 +
+ C = Oc^C = --
:J^[(5X + 3 ) V 5 ^
+ (5x + l ) / 5 x T T ]
T i m h a m so y = f(x) neu biet:
Giai
X"
12
D o n g nhat ta c6: a = — ; b = - — '
,
b
Ta c6: f '(x) = ax + —
-5ax2 + (12a - 3b)x + 6b - c = 2x(3 - x), V \ 3
- + b + c = 2
F(\ cua f(x) biet F( —) = 0
lis giai thiet ta c6:
6
—
2
b+ c = 4
a + b = 0
Giai
^
2
Bai 3. Cho f(x)
5
4
V3
1
1
-
f ' ( x ) = 4 N / x - X va f(4) = 0
4
1
V5x + 3 - V 5 x + l
Giai
. T i m nguyon ham F(x) cua f(x) biet F(0) = 0
Giai
X-
38
1
3
3
+c = o
+C=0 « C =
/-
x-
40
, Vgy: f ( x ) = _ x V x - y - y
- ^
J
+ C
3V3+I
Bai 6; Tim ham so y = f(x) biet r3ng: f (x) = ifx +
Giaj
4
+—
2
g^_g: H m hg nguyen ham ciia cac ham so'
7t ,
sin X - c o s x
b) l(x) = cot2(2x+ - )
a)f{x)=4
s i n x + cosx
Gi.ii
1 1 1
1
f(l) = 2 o - + - + - + C = 2<:=>c= ^ '
4 4 2
2
Vay f(x)= — x ^ + —x^ + — x^ + —
4
4
2
2
i)
Bai 7: Chung minh F(x) = I x | - ln(l + | x | ) Li mot ngii ven ham aia: f(x) = —
1+
ff(x)dx =
cotx
b) f(x) =
khi x = ()
0
C
sin"(2x + - )
4
2x +
A)
Dodo: ff(x)dx = l f
sin'^ 2x +
4]
= f(x)
Khix>0:F"(x) = l -
_|„i^i,, ^ + ^.^^^X +
khi
X
d u = dx
d v = e^^dx =>
^ + C = - ( x + I )e-'' + C
pai 22: D u n g p h u a n g phap lay nguyOn h a m t i i n g p h a n hay t i m h p nguyen
Gi.ii
ham ciia:
D a t t = 2cosx - 1 => d t = -2sinxdx
b) y = x2 ln3x
a)y = x s i n -
1
sinxdx = — d t
2
Giai
a) Dat u = X
d u = dx
X
X
COS"
x
fe'dt = e ' + C = e"'^"^+C
ham ciia cac h a m so':
a) y = yjx Inx
V
Bai 23: Dat L =/x"e«dx
Bai 2 1 : D u n g p h u o n g phap lay nguyCn h o n i l u n g phan hay t i m h p nguyen
a) D a t u = Inx => d u =
dx
a) C h u n g m i n h : In = x " ^ - n l i . - i , V n e N "
a) In-.= J x " V d x = > ( l „ . , ) ' = x"-'.e''
Ta c6: [x'^e" - nin-i]' = n . x " - ' . e" + e^x" - n.x" ' .
b) t = l x V d x
V =
f^/x I n x d x = — x V x i n x - — x V x + C '
J
-1
—^— = - X
snr X
cot
X
+ col xdx
-x
Cut \
f
= eMn(l + e^) -
sm x
e'
dx = e>^ln(l + e^) -
+
ln(sin x ]
^ ,
dx
r
Bai29:
d u = cotxdx
cos
a =1
o
b = l
-a = - l
cd(sina) _ cosa
cosx
1 .
+—sinaln
2
1 + sinx
1-sinx
+ C
b)
X--2X-1
dx =
dx
x(x--F)
Gi.ii
c
-dx
c
x"-2x-l
a
b
^
= _ +
+
x(x"-l)
x
x-fl
x-1
dx
-"l-siirix
+ C
sin2x +
Giai
X
F '(x) = ^('') Vx e R
2.\
2 a - b = 7 <=>
b =
- 3
b-c--4
c=
1
(4 COS" x - 3 ) s i n 2 x
F'(x) = 2x V 4 - X - =f(x)
g ^ :
C h o f(x) =
l-2sinx
Tim mpt nguyen ham F(x) ciia f(x) bict
F'(-2*)=
lim
= lini - ( x - 2 ) > y 4 - x -
Do do F(x) la mpt nguyen ham ciia f(x) treii [-2; 2]
Bai 32: Tinh
|f(x)dx = - — cos2x + sinx - — sin3x + C
2
3
f-^^ilil_dx
•"x" + 5 x + 6
F(0) = - - + C = 0<r>C= ^ 2
2
Ciai
4x + l l
.
Jx'+Sx + e
c2(2x + 5) + l ,
•'x-+5x + 6
2x+5
•'x-+5x + 6
^
r