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问题: log的计算

lg4+lg5*lg20+(lg5)的平方

解答:

lg4+lg5*lg20+(lg5)^2
= lg4+lg5*[lg20+lg5]
= lg4+lg5*[lg(20*5)]
= lg(2*2)+lg5*[lg(100)]
= 2lg2+2lg5
= 2(lg2+lg5)
= 2lg10
= 2