lg5·lg20+(lg2)^2

来源：学生作业帮助网编辑：作业帮时间：2024/05/03 07:19:52

lg5·lg20+(lg2)^2
lg5·lg20+(lg2)^2

lg5·lg20+(lg2)^2
lg5·lg20+(lg2)^2=（lg10-lg2）*（lg10+lg2）+(lg2)^2
=（1-lg2）*（1+lg2）+(lg2)^2
=1

=lg5(lg2+lg5+lg2)+lg2*lg2=lg5*lg2+lg5*lg5+lg2*lg2+lg5*lg2=lg5(lg2+lg5)+lg2(lg2+lg5)=lg5+lg2=1

lg5·lg20+(lg2)^2 (lg2)^2+lg5*lg20 (lg2)^2+lg20*lg5 （lg2)^2+lg5·lg20-1=? lg2*lg50+lg5*lg20-2lg5*lg2 lg5^2+lg4+lg5*lg20+(lg2)^2 (lg2)^2+lg20*lg5+(lg5)^2 lg5^2+lg4+lg5*lg20+(lg2)^@ 问道对数题 lg2*lg50+lg20*lg5-2lg5*lg2 lg2·lg50-lg5·lg20-lg4 (lg2)^2 lg5×lg20－1 lg5*lg20+(lg2)^ lg2*lg2+lg20*lg5=? lg5^2+2/3lg8+lg5*lg20+lg2^2 lg5^2+lg8^2/3+lg5*lg20+(lg2)^2=? （lg5)平方+2/3lg8+lg5乘lg20+（lg2)平方 lg5²+2/3lg8+lg5*lg20+(lg2)² lg5²+2/3lg8+lg5×lg20+(lg2)²