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问题: 计算;[(lg√27)+lg8-(lg√1000)]/lg1.2的值

解答:

lg√27=(1/2)lg27=(3/2)lg3,

lg8=3lg2,

lg√1000=(1/2)lg1000=3/2,

lg1.2=lg[(3*4)/10]=lg3+lg4-lg10=(lg3)+2(lg2)-1,

[(lg√27)+lg8-(lg√1000)]/lg1.2
=(3/2)[(lg3)+2(lg2)-1]/[(lg3)+2(lg2)-1]
=3/2.