Bài kiểm tra 45 phút môn Đại số 8

Bài Kiểm tra 45 phút
 Môn Đại số
 Họ và tên : .................................... .................. Lớp :8a 
 Lời phê Điểm 
Câu1)Kết quả phép tính 20a2b2c3 :(5ab2c) là
 A.4abc B.20ac C.20ac2 D.4ac2
Câu 2) Kết quả phép tính (x +y)2 là
A. x2+y2 B. x2+ 2xy +y2 C. x2+ xy +y2 D. x2 + 2xy +y2 
Câu 3) Kết quả phép tính(2a-b)3 là
A.8a3-b3 B.2a3-3a2b+3ab2 –b3 D. 8a3-12a2b+6ab2 –b3 C. 8a3+12a2b+6ab2 +b3
Câu 4) Kết quả phép tính(3x2-12):(x-2) là
A.3(x-2) B.3(x+2) C.x-2 D.x+2
Câu 5)Điền đa thức thích hợp vào chỗ chấm (...)
 ( ... )(x2+x+1) = x3+3x2+3x+2
Câu 6)Làm các phép tính sau:
a)(2x+1)(3x+1)-(6x+1)(x+1) =......................................................................................... ....................................................................................................................................................................................................................................................................................................................................................................................................................................................................................................................................................................................................................................................................................................................................................................................................................................................................................................................................................................................................
b)(3x3+3x-1):(3x+1)
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Câu 7)Phân tích đa thức sau thành nhân tử:
a)4x2-4xy-8y2= ................................................................................................................
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b)4ab+a2-3a-12b = ..........................................................................................................
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c) x3+3x2+3x+1-27y3=.....................................................................................................
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Câu 8)Tìm x biết: x3-1 = 0
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Câu 9)Chứng minh rằng với mọi số tự nhiên lẻ thì n3-n luôn chia hết cho 24.
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