lg2lg2lg250+lg5lg5lg40

来源：学生作业帮编辑：作业帮分类：数学作业时间：2024/11/08 17:50:40

lg2*lg2*lg250+lg5*lg5*lg40
我一窍不通

g250=lg(10*5^2)=lg10+lg5^2=1+2lg5
lg40=lg(10*2^2)=1+2lg2
原式=lg2*lg2*(1+2lg5)+lg5*lg5*(1+2lg2)
=lg2*lg2+2lg2*lg2*lg5+lg5*lg5+2lg2*lg5*lg5
=lg2*lg2+2lg2*lg5(lg2+lg5)+lg5*lg5
=lg2*lg2+2lg2*lg5+lg5*lg5
=(lg2+lg5)^2
=1

lg2*lg2*lg250+lg5*lg5*lg40 (lg2)^2*lg250+(lg5)^2*lg40= （lg2）²×lg250+（lg5）²×lg40 （lg2)平方.lg250+(lg5）平方.lg5 计算:lg2+lg5-lg8/lg50-lg40 lg2*lg5/2+lg0.2*lg40 lg5+lg5*lg2+lg2*lg2 lg2^2+lg2*lg5+lg5=lg2(lg2+lg5)+lg5 lg2(lg5-lg2)-lg5(lg5+3lg2)等于计算：(lg5)^2 +lg2 *lg5 (lg5)^2+lg5.lg2= lg2(1+lg5)+(lg5)^2