Trêng THCS lª thanh
|
|
|
Hä vµ tªn: ..............................
|
KiÓm tra ch¬ng I
|
|
Líp: 8 ......
|
M«n: §¹i sè 2
Thêi gian: 45 phót
|
|
§iÓm
|
Lêi phª cña thÇy gi¸o
|
Bµi 1: §iÒn dÊu ''x'' vµo « thÝch hîp.
|
C©u
|
Néi dung
|
§óng
|
Sai
|
-
|
(x - 1)2 = 1 - 2x - x2
|
|
|
-
|
(x + 2)2 = x2 + 2x + 1
|
|
|
-
|
(a - b)(b + a) = (b - a)2
|
|
|
-
|
- x2 + 6x - 9 = - (x - 3)2
|
|
|
-
|
- (x - 5)2 = (- x + 5)2
|
|
|
-
|
(x3 - 1) : (x - 1) = x2 + 2x + 1
|
|
|
-
|
- 3x - 6 = - 3 (x - 2)
|
|
|
-
|
(x3 + 8) : (x2 - 2x + 4) = x + 2
|
|
|
Bµi 2: Rót gän c¸c biÓu thøc sau:
a. (2x + 1)2 + 2 (4x2 - 1) + (2x - 1)2
.................................................................................................................. .................................................................................................................. .................................................................................................................. .................................................................................................................. .................................................................................................................. .................................................................................................................. ..................................................................................................................
b. (x - 3)(x + 3) + (x + 3)2
.................................................................................................................. .................................................................................................................. .................................................................................................................. .................................................................................................................. .................................................................................................................. ..................................................................................................................
Bµi 3: Ph©n tÝch c¸c ®a thøc sau thµnh nh©n tö.
a. 3x2 - 3y2 - 12x + 12y
.................................................................................................................. .................................................................................................................. .................................................................................................................. .................................................................................................................. b. x4 + 1 +2x2
.................................................................................................................. .................................................................................................................. .................................................................................................................. .................................................................................................................. ..................................................................................................................
Bµi 4: Lµm tÝnh chia: (x4 + 2x3 + 10x - 25) : (x2 - 5)
.................................................................................................................. .................................................................................................................. .................................................................................................................. .................................................................................................................. .................................................................................................................. .................................................................................................................. .................................................................................................................. .................................................................................................................. .................................................................................................................. ..................................................................................................................Bµi 5:
T×m sè a ®Ó ®a thøc (x3 - 3x2 + 5x + a) chia hÕt cho ®a thøc (x- 7)
.................................................................................................................. ..Bµi 5 a:Cho tam gi¸c ABC
Cã ba c¹nh lµ a,b,c tho¶ m·n 
Th× tam gi¸c lµ tam gi¸c g×.
b:T×m x, biÕt
.............................................................................................................................................................................................................................................................................................................. ………………………………………………………………………………..……………………………………………………..……………………….………………………………………………………………………….…………………………………………………………………..................................................................................................................................................................................................... .....................................................................................................
