Giao an dai 8 chuong 2

Trường: THCS Văn Khê
Lớp : 8
Họ tên :............................
TRA 15 phútI Số
Điểm



Lời phê


Bài 1:Cho các đa thức sau đã được phân tích thành nhân tử , hãy họn đáp án đúng(3điểm)
1/ 4x2-12x+9=
A. (2x+3)2 B.-(2x-3)2 C.(2x-3)2 D . (4x-3)2

2/ x3-6x2y+12xy2-8y3=
A.(x-y)3 B.x3-(2y)3 C.(2x-y)3 D.(x-2y)3

3/5x2-10x+10xy-20y=
A.5(x-2)(x+2y) B.5(x-2)(x-2y) C.5(x+2)(x+2y) D.5(x+2)(x-2y)

Bài 2: Tìm biết:(6điểm)
a/ 3x(x-7)-x(7-x)=0 b/ x2- 6x+8=0
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c/ (2x-3)2=(x+5)2
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Bài 3: Tìm max hoặc min nếu có của:(1điểm)
A
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