Bài tập Đại số Lớp 8

BÀI TẬP Bài 1: Rút gọn phân thức:

a)

5

2 2 14 (2 3 ) 21 (2 3 ) xy x y x y x y   b)

2

2 4 4 y xy y xy   c)

3

3 8 (3 1) 12 (3 1) xy x x x



 d)

2

2

25 5 x x x  

e) 2 3

3 2

24 21

y x

y x f)    

2 2

2 2 3

20

15

y x y x

y x xy



 g) 2 2

3

20

25

y x

y x h)    

2 2

2 2 3

15

18

y x y x

y x xy





Bài 2: Quy đồng mẫu thức của các phân thức sau:

a) 3 2 4

5

y x và 2 3 3

4

y x b) 2 3 4

3

y x và 3 3

2 xy

c) 2 1 x x

x



 và 2 2 4 2

2

x x x

 

 d) 4 2 6

1 y x x  và 3 4

2 xy BÀI LÀM

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