( ) ( )2 2− − + = −) 2 1 2 1 4( 3)A X X X+ + + = −2 3 3 2X XB X) 2,5 13 21 1 1 1+ + +) 5 4 4 3 3 2 2 1C X X X X X X X X( ) ( ) ( ) ( ) ( ) ( ) ( ) ( )+ + + + + + + +2 2 2 2 2 2 2 2

Bài2: Giải phương trình:

( ) ( )

2

2

+

=

) 2

1

2

1

4(

3)

a

x

x

x

+

+

+

=

2

3 3

2

x

x

b

x

)

2,5

1

3

2

1

1

1

1

+

+

+

)

5

4

4

3

3

2

2

1

c

x

x

x

x

x

x

x

x

( ) ( ) ( ) ( ) ( ) ( ) ( ) ( )

+

+

+

+

+

+

+

+

2

2

2

2

2

2

2

2