log₂1-lg3×log₃2-lg5原式=0-(lg3×log₃2+lg5）=0-﹙㏒₃3／㏒₃10 ×log₃2 + ㏒₃5／㏒₃10﹚=0-[1／㏒₃10 （㏒₃2 +㏒₃5）]=0-（1／㏒₃10 ×...