A) X – 3 – 3 X – 3 X2 3X 99X 12 15 B) 4X2 81 0C) X X – 5X 5 – X – 2 X2 2X 43 D) 25X2 – 20E) X 2 2  2 – 1X 2 F) X 2 –2 X  4 0

Bài 2: Tìm x, biết:

a)

x

– 3 –

 

3

x

– 3

 

x

2

3

x

9

9

x

1

2

15

b)

4

x

2

81

0

c)

x x

– 5



x

5 –

 

x

– 2

 

x

2

2

x

4

3

d)

25

x

2

– 2

0

e)

x

2

 

2

2 – 1

x

2

f)

x

2 –

2

x

 

4

0