logaclogbc=1,logbc-logac=±√(logbc-logac)^2=±√(logbc+logac)^2-4logaclogbc=±√[(3/2)^2-4]=±5/2.
log(a/b) C=1/logc(a/b)=1/(logca-logcb)=1/(1/logac-1/logbc)=logaclogbc/(logbc-logac)=±5/2.