De thi

Trường THCS bài kiểm tra đại số 15 phút ( Bài số2 )
hoằng phu
Ngày ……….tháng…… năm 2012
Họ và tên. . . . . . . . . . . . . . . . . . . . . . . . . . lớp 8....


Điểm
Lời phê của thầy, cô giáo
chữ kí của giáo viên

 I. TRẮC NGHIỆM (3đ):
Khoanh tròn vào chữ cái đứng trước câu trả lời đúng câu trả lời đúng.
Câu 1: Điều kiện để cho biểu thức
là một phân thức là:
A. x
1; B. x = 1; C. x
0 D. x = 0
Câu 2: Phân thức bằng với phân thức
là:
A.
B.
C.
D.

Câu 3: Phân thức đối của phân thức
là:
A.
B.
C.
D.

II. TỰ LUẬN (7đ):
Bài 1: (2 điểm). Rút gọn phân thức:



Bài 2: (5điểm). Cho phân thức: A =

a) Với điều kiện nào của x thì giá trị của phân thức được xác định?
b) Tính giá trị của phân thức A tại x = 1999.













HƯỚNG DẪN CHẤM VÀ THANG ĐIỂM

I. TRẮC NGHIỆM (3đ): Mỗi câu 1,0 đ

Câu
1
2
3

Đáp án
A
C
C

II. TỰ LUẬN (7đ):
Bài 1: (2đ) Rút gọn phân Thức

(1,5đ)

(1,5đ)
Bài 2
A =

a) Đ K X Đ : x + 2
0
x


b) A =
=
= x + 2
Tại x = 1998 thì A = 1998 + 2 = 2000


1đ
2đ

1đ




























Bài làm
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