lg2^2+lg2*lg5+lg5=lg2(lg2+lg5)+lg5

来源：学生作业帮编辑：拍题作业网作业帮分类：数学作业时间：2024/04/30 04:34:02

lg2^2+lg2*lg5+lg5=lg2(lg2+lg5)+lg5
这个过程中,lg2的平方怎么没了?

(lg2)^2=lg2*lg2
(lg2)^2+lg2*lg5+lg5(
=lg2*lg2+lg2*lg5+lg5(前两项提取公因式lg2)
=lg2(lg2+lg5)+lg5
=lg2*1+lg5
=1

lg2^2+lg2*lg5+lg5=lg2(lg2+lg5)+lg5 lg5+lg5*lg2+lg2*lg2 (lg5)^2+lg5.lg2= (lg2)^2+lg2*lg5+(lg5)^2= 2lg5*lg2= =(lg5)^2+lg2×lg5+lg2 =lg5×(lg5+lg2)+lg2麻烦问一下,这是咋做的计算：(lg5)^2 +lg2 *lg5 lg2(1+lg5)+(lg5)^2 2lg2（lg2+lg5)+2lg5得数 (lg5)平方+2*lg5*lg2+(lg2)平方计算 lg5^2+lg2*lg5+lg2 lg2 2+lg4*lg5+lg2