【解析】 (1) 1l_g2+3l_y5-I_g =11g2+3lg5-1gi^(-1) =41g2+31g5+1g5 =41g2+41g5 =1(1g2+1g5) =4lg10 =I 综上所述,结论是:4 (2)/g/27+1g8-1g/1000 1g1.2 _lg32+1g2'-1g10 3lg3+3lg2-3 1g1.2 31g3+3 lg+-3 3/2(lgy+lg1-lg10) lg1.2 3/2lg(3*1÷...