lg25+(2/3)lg8+lg5.lg20+(lg2)^2
问题描述：
lg25+(2/3)lg8+lg5.lg20+(lg2)^2
答
lg25+(2/3)lg8+lg5.lg20+(lg2)^2
=2lg5+2lg2+lg5（1+lg2)+(lg2)²
=2+lg5+lg5lg2+lg²2
=2+lg5+lg2
=2+1
=3