2 log akar 8+2 log akar 2-2 log 16

²log √8 + ²log √2 - ²log 16
= ²log (√8×√2) - ²log 16
= ²log √16 - ²log 16
= ²log 4 - ²log 16
= ²log (4/16)
= ²log ¼
= ²log 2^-2
= (-2) ²log 2
= (-2) (1)
= -2
^ tanda pangkat