= = = ( ) ( )LOG 1 LOGX U UA AX A U A U
3.4.Đạo hàm: = = =
( ) ( )
log 1 logx u ua
a
x a u a u.ln .ln−
n
n
1
(ln ) lnu n u= = (ln ) 1, ( 0) (ln )u ux x ux ua
a
x a u a u.ln .ln−
n
n
1
(ln ) lnu n u= = (ln ) 1, ( 0) (ln )u ux x ux u