X24 2X4  1 X4X3 (ĐK

11)

x

²

⁴

²



x

⁴

 

¹

x

⁴



x

³

(ĐK : x

⁴

^

2)



⁴

⁴



⁴



( x

^

0 )

2

2

x

x

1

x

x











2

x

x

1

x

4

4

2

2





 

x



Ta cã:

¹

₂

x

²

²

x





Dấu bằng xảy

x

²

¹

₂





x



x

²



1

(1)

Mặt khác:



⁴

²

^

^x

⁴

^

^x



²

^

⁽

¹

²

^

¹

²

⁾



²

^

^x

⁴

^

^x

²



x

x

x

x

x

x

2

4 2

4.2 2

16



















(2)

^



⁴

⁴

 

⁴

⁴

²



²

^

⁴

⁴

^

4

2

4

x

x

2

16 2





 



Dấu “=” xảy khi x = 1

Từ (1)(2)



x



1