80 BT PT và Hệ PT (Hay)

Bµi tËp hÖ ph¬ng tr×nh
Gi¶i c¸c hÖ ph¬ng tr×nh sau :
1,
+ + = −

−

+ = −

2 2
1
( 99)
6
x xy y
MTCN
x y y x
2,

+ =

−

− + =


2 2
4 2 2 4
5
( 98)
13
x y

NT
x x y y
3,

+ =

−

+ =


2 2
3 3
30
( 93)
35
x y y x
BK
x y
4,

+ =

−

+ = +


3 3
5 5 2 2

1
( 97)
x y
AN
x y x y
5,

+ + =

−

+ + =


2 2
4 4 2 2
7
( 1 2000)
21
x y xy
SP
x y x y
6,
+ + =

−

+ + + =

2 2

11
( 2000)
3( ) 28
x y xy
QG
x y x y
7,

+ = +

−


+ =

7
1
( 99)
78
x y
y x
xy
HH
x xy y xy
8,

+ + =


−



+ + =


2 2
2 2
1
( )(1 ) 5
( 99)
1
( )(1 ) 49
x y
xy
NT
x y
x y
9,

+ + + =


−


+ + + =


2 2
2 2

1 1
4
( 99)
1 1
4
x y
x y
AN
x y
x y
10,
+ + =

−

+ + =

2
( 2)(2 ) 9
( 2001)
4 6
x x x y
AN
x x y
11,

+ + + + + + + + + =

−


+ + + − + + + + − =


2 2
2 2
1 1 18
( 99)
1 1 2
x x y x y x y y
AN
x x y x y x y y
12,
+ + =

−

+ + − =

2
(3 2 )( 1) 12
( 97)
2 4 8 0
x x y x
BCVT
x y x
13,

+ =

−


+ =


2 2
2 2 2
6
( 1 2000)
1 5
y xy x
SP
x y x
14,
+ =

−

+ + =

2 2 3 3
4
( 2001)
( )( ) 280
x y
HVQHQT
x y x y
15,

− = −


−

− = −


2 2
2 2
2 3 2
( 2000)
2 3 2
x x y
QG
y y x
16,

= −

−

= −


2
2
3
( 98)
3
x x y
MTCN
y y x

17,

+ =


−


+ =


1 3
2
( 99)
1 3
2
x
y x
QG
y
x y
18,

= +

−

= +



3
3
3 8
( 98)
3 8
x x y
QG
y y x
19,

+ =


−


+ =


2
2
3
2
( 2001)
3
2
x y
x
TL
y x

y
20,

+ + − =

−

+ + − =


5 2 7
( 1 2000)
5 2 7
x y
NN
y x
21,

+
=


−

+

=


2

2
2
2
2
3
( 2003)
2
3
y
y
x
KhèiB
x
x
y
22,

− =

−

− − =


2
2 2
3 2 16
( )
3 2 8
x xy

HH TPHCM
x xy x
23,

+ =

−

+ = −


3 3 3
2 2
1 19
( 2001)
6
x y x
TM
y xy x
24,

− + =

−

− + =


2 2
2 2

2 3 9
( )
2 13 15 0
x xy y
HVNH TPHCM
x xy y
25,

− =

−

+ =


2 2
2 2
2 ( ) 3
( § 97)
( ) 10
y x y x
M C
x x y y
Bài tập phơng trình -bất phơng trình vô tỉ
Giải các phơng trình sau:
1,
3 6 3x x+ + =
2,
9 5 2 4x x+ = +
3,

4 1 1 2x x x+ =
4,
2 2
( 3) 10 12x x x x =
5,
3 3
4 3 1x x+ =
6,
3 3 3
2 1 1 3 1x x x + = +
7,
2 2 1 1 4( 2005)x x x khốiD+ + + + =
8,
2 1 2 1 2( 2000)x x x x BCVT+ =
9,
3(2 2) 2 6( 01)x x x HVKTQS+ = + +
10,
2 2
2 8 6 1 2 2( 2000)x x x x BK+ + + = +
11,
2 2 2 2
5 5
1 1 1( 2001)
4 4
x x x x x PCCC + + = +
12,
2
( 1) ( 2) 2 ( 2 2000 )x x x x x SP A + + =
13,
2 2

2 8 6 1 2 2( 99)x x x x HVKTQS+ + + = +
Tìm m để phơng trình :
14,
2
2 2 1( 2006)x mx x KhốiB+ + = +
có 2 nghiệm phân biệt
15,
2
2 3 ( )x mx x SPKT TPHCM+ =
có nghiệm
16,
2
2 3 ( 98)x mx x m GT+ =
có nghiệm
Giải các phơng trình sau :
17,
2 2
11 31x x+ + =
18,
2
( 5)(2 ) 3 3x x x x+ = +
19,
2 2
3 3 3 6 3( 98)x x x x TM + + + =
20,
2 3
2 5 1 7 1x x x+ =
21,
2 3
2 4 3 4x x x x+ + = +

22,
2 2
3 2 1( 99)x x x x NT + + =
23,
1 4 ( 1)(4 )( 20001)x x x x NN+ + + +
24,
2 2
4 2 3 4 ( Đ 2001)x x x x M C+ = +
25,
2
2 4 6 11x x x x + = +
26,
2
2 3 5 2 4 6 0( 01)x x x x GTVT TPHCM + + =
27,
2
3 2 1 4 9 2 3 5 2( 97)x x x x x HVKTQS + = + +
28,
2
7 4
4 ( Đô Đô 2000)
2
x x
x DL ng
x
+ +
=
+
29,
3 3

2 1 1
2( 95)
1 2 2
x
GT
x x
+ + =
+
30,
2
2 2
1
x
x
x
+ =

31,
2 2
1 1 (1 2 1 )x x x+ = +
32,
2 2
(4 1) 1 2 2 1(Đ 78)x x x x ề + = + +
33,
2 2
3 1 ( 3) 1( 01)x x x x GT+ + = + +
34,
2 2
2(1 ) 2 1 2 1x x x x x + =
35,

2
1 1( 98)x x XD+ + =
36,
3
2 1 1( 2000)x x TCKT =
37,
3
7 1( 96)x x Luật+ =
38,
3 3
3 3
7 5
6 ( Đ á )
7 5
x x
x C KiểmS t
x x

=
+
39,
3
3
1 2 2 1x x+ =
Gi¶i c¸c bÊt ph¬ng tr×nh sau :
1,
( 1)(4 ) 2( § 2000)x x x M C− − > − −
2,
1 3 4( 99)x x BK+ > − + −
3,

3 2 8 7 ( 97)x x x AN+ ≥ − + − −
4,
2 3 5 2 ( 2000)x x x TL+ − − < − −
5,
2 2
( 3) 4 9(§ 11)x x x Ò− − ≤ −
6,
2
1 1 4
3( 98)
x
NN
x
− −
< −
7,
2
2
4( 01)
(1 1)
x
x SPVinh
x
> − −
+ +
8,
2 2
12 12
( 99)
11 2 9

x x x x
HuÕ
x x
+ − + −
≥ −
− −
9,
2 2 2
3 2 6 5 2 9 7( 2000)x x x x x x BK+ + + + + ≤ + + −
10,
2 2
4 3 2 3 1 1( 2001)x x x x x KT− + − − + ≥ − −
11,
2 2
5 10 1 7 2 (§ 135)x x x x Ò+ + ≥ − −

12,
2
4 (4 )(2 ) 2 12(§ 149)x x x x Ò− − + ≤ − −
13,
3 2
( 1) ( 1) 3 1 0( 99)x x x x XD+ + + + + > −
14,
3 1
3 2 7( ¸ ª 2000)
2
2
x x Th iNguy n
x
x

+ < + − −
15,
2 2
( 4) 4 ( 2) 2( 99)x x x x x HVNH− − + + − < −