log0.8 0.5怎么求?已知lg2=0.3010lg0.5/lg0.8

来源:学生作业帮助网 编辑:六六作业网 时间:2024/05/24 11:48:26
log0.80.5怎么求?已知lg2=0.3010lg0.5/lg0.8log0.80.5怎么求?已知lg2=0.3010lg0.5/lg0.8log0.80.5怎么求?已知lg2=0.3010lg0

log0.8 0.5怎么求?已知lg2=0.3010lg0.5/lg0.8
log0.8 0.5怎么求?已知lg2=0.3010
lg0.5/lg0.8

log0.8 0.5怎么求?已知lg2=0.3010lg0.5/lg0.8
lg0.5/lg0.8
=lg(1/2)/lg(4/5)
=-lg2/(lg4-lg5)
=-lg2/(2lg2-(1-lg2))
=lg2/(3lg2-1)
即:原式=0.3010/(3*0.3010-1)=-3.103

lg0.5/lg0.8
=lg(1/2)/lg(4/5)
=-lg2/(lg4-lg5)
=-lg2/(2lg2-(1-lg2))
=lg2/1-3lg2