2Log 8 + 2Log 4 – 3Log 81 + 5Log 25 = .. ??

2Log 8 + 2Log 4 – 3Log 81 + 5Log 25
= 3 + 2 – 4 + 2
=3

2Log 8 = 2Log 2^3 = 3.
Maka, jawabannya: 3 + 2 – 4 + 2 + 3.