(lg5)^2+2lg-(lg2)^2 怎么算
问题描述:
(lg5)^2+2lg-(lg2)^2 怎么算
答
lg5)2 2lg2-(lg2)2=(lg5 lg2)(lg5-lg2) 2lg2 =lg10* lg2.5 2lg2 =lg2.5 lg2 lg2 =lg(2.5*2*2) =lg10 =1 通过分解因式,提取,合并
(lg5)^2+2lg-(lg2)^2 怎么算
lg5)2 2lg2-(lg2)2=(lg5 lg2)(lg5-lg2) 2lg2 =lg10* lg2.5 2lg2 =lg2.5 lg2 lg2 =lg(2.5*2*2) =lg10 =1 通过分解因式,提取,合并