3log125 . akar5log81 - 5log625 =

    [tex]^3log5^3 . ^{ 5^{ \frac{1}{2}}}log 3^{4} - {^{5}log5^{4} [/tex]
=  [tex] \frac{3}{ \frac{1}{2} } . 4 - 4 = 24-4 = 20 . ^3log5.^5log3 - ^5log5[/tex]
= 20 . 1 - 1 = 20 - 1 = 19

Kalo gk salah ini gan...