( 2+ 3) (X + 2− 3)X =4 GIẢI

Bài 1:

(

^{2+ 3}

) (

^{x + 2− 3}

)

^{x =4} Giải: x x x2 3 2 3 4 2 3 1 4

( ) ( ) ( )

+ + − = ⇔ + + x =

( )

2 3+ ðặt ^t=

(

^{2+ 3}

)

^x

⁽

^t>0

⁾

^{ta có :t+1}_t ^=4⇔t_t⁼²₂^{− 3}₃ = +x + = −2 3 2 3  = −2 ⇔ Khi ñó ta có :

( )

x x2 3 2 3 2  =+ = +