tolong no 20 dan 21 beserta cara kerjanya

20. ²log 5.5 log 6.6 log 7.7 log 8 = ²log 8 = ²log 2³ = 3
Jawab : E.

21. ³log 108 - ³log 4 + ³log 72 - ³log 8 = ³log ((108/4.72) /8) = ³log (108.(18)/8) = ³log (243) = ³log 3^5 = 5
Jawab : E.