一道数学题log2=a,log3=b.那么log4/15等于?

分类: 作业答案 • 2021-12-20 05:56:38

问题描述：

答

3a-b+1

答

log4/15=log4-log15=2*log2-log[10*(3/2)]=2*log2-log10-log3/2=2*log2-log10-log3+log2=3*log2-log3-log10=3a-b+1

答

log4/15
= log8/30
=log 8 - log 30
=3log2 - (log3 + log 10)
=3a-b-1
不理解就追问,理解了请采纳!

答

是lg2=a,lg3=b吧
lg(4/15)
=lg(8/30)
=lg8-lg30
=lg2³-lg(3*10)
=3lg2-lg-lg10
=3a-b-1