计算:lg25+2/3lg8+lg5乘以lg20+lg^22
问题描述:
计算:lg25+2/3lg8+lg5乘以lg20+lg^22
答
lg25+2/3lg8+lg5乘以lg20+lg^22
=2lg5+2lg2+lg5*(2lg2+lg5)+lg2*lg2
=2(lg5+lg2)+(lg5)^2+2lg2*lg5+(lg2)^2
=2lg10+(lg5+lg2)^2
=2+1^2=3