2 log 8-2 log 32 +2 log 1/16

²log 8 - ²log 32 + ²log 1/16
= ²log(8/32) + ²log 1/16
= ²log 1/4 + ²log 1/16
= ²log(1/4×1/16)
= ²log(1/64)
= ²log 2^(-6)
= -6