log27 $log-27 5$ =$\frac{1}{3}$$log_3 5=a suy ra $log_3 5$ =3alog27 = $\frac{1}{3}$ $log_3 5 $ =a $\Rightarrow$ $log_3 5$ =3a log27 của 5 =$\frac{1}{3}$$log_3 5$ =a suy ra $log_3 5$ = 3a
$log_8 7$ =$\frac{1}{3}$ $log_2 7$ =b $\Rightarrow$ $log_2 7$ = 3b
$log_2 3$=c
$log_6 35$ = $\frac{log_2 35}{log_2 6}$=$\frac{log_2 5+log_2 7}{log_2 2+log_2 3}$= $\frac{\frac{log_3 5}{log_3 2}+log_2 7}{1+log_2 3}$
=$\frac{3ac+3b}{1+c}$