Toán 8

THCS Lý thường Kiệt KIỂM TRA 1 TIẾT
Họ tên học sinh:............................................... MÔN: ĐẠI SỐ
Lớp: 8/11 ( BÀI SỐ 1 )
I/PHẦN TRẮC NGHIỆM: (2,5đ)
1.Đơn thức ( 8x3y2z3t2 chia hết cho đơn thức nào ?
A. (2x3y3z3t3 B. (9x3yz2t C. 4x4y2zt D. 2x3y2z2t3
2.Biểu thức rút gọn của : (2m ( 3)(m + 1) ( (m ( 4)2 – m(m + 7) là :
A. m + 2 B. 6 C. (19 D. (2m + 3.
3.Phép chia: (x2 – 4x + 3) : (x – 3) cho kết quả :
A. x + 1 B. x + 4 C. x – 1 D. x – 4
4Nếu x3 + 9x = 0 thì giá trị của x là:
A. x = 0 B. x = 3 C. x = ( 3 D. Cả 3 giá trị trên.
5Đẳng thức nào đúng ?
A. (x – 2)(x2 + x + 4) = x3 – 8 B. 9x2 – 12x + 4 = (3x – 2)2
C. (2x – 3)(2x + 3 = 2x2 – 9 D. x3 – 3x2 + 3x + 1 = (x – 1)3
II/TỰ LUẬN: (7,)
Bài 1: ( ) Phân tích đa thức sau thành nhân tử
a/ x2 - 6x + 9 - y2
b/ 6x2+ 6xy - 12x -12y
Bài 2: (3đ)Rút gọn biểu thức:
a/ (3x-1)2 - 2 (3x-1)(2x+3)+ (2x+ 3)2
b/ (x-2)3-x(x+1)(x-1)+6x(x-3)
Bài 3: (1,5đ)Làm tính chia:
(x5 – 2x4 + 4x3 – 7x2 + 3x – 1) : (x3 – 2x2 + x – 1)
Bài 4: (1đ) Chứng minh rằng:
x2 + xy + y2 + 1 > 0 với mọi x, y
BÀI LÀM
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