log (log2)^2 - (log4)(log20) + (log20)^2

分类: 作业答案 • 2021-12-19 17:21:48

问题描述：

log
(log2)^2 - (log4)(log20) + (log20)^2

答

原式=(log2)^2 - 2(log2)(log20) + (log20)^2=（log2-log20)^2=（log10）^2=1

答

(log2)^2 - (log4)(log20) + (log20)^2
=(log2)^2 - 2 (log2)(log20) + (log20)^2
=[lg2-lg20]^2
=[-lg10]^2
=[-1]^2
=1