dgzm.net
当前位置:首页 >> 求值:log以3为底根号27的对数+lg25+lg4+7的log7为... >>

求值:log以3为底根号27的对数+lg25+lg4+7的log7为...

你参考看看~

你把题看错了 应该是4次根号下27 可以化成3的3/4次方 原式=log 3^(-1/4)+lg(2.5*4)+2 3 =-1/4+lg10+2 =-1/4+1+2 =11/4

log7=log(7/1)=log7-log1=log7-0=log7

楼主你好!很高兴为你解答: 根据对数恒等式:a^log a (N)=N,也就是说7的log75=5 那么7的1+log75=7的1乘以7的log75=7乘以5=35 这样解说希望楼主能理解,不清楚的话欢迎追问交流,希望能帮到楼主~

原式=3+(lg25+lg4)+2+1 =3+2+3 =8.

log 3 27 +lg25+lg4+7 log 7 2 +(-9.8) 0 = lo g 3 3 3 2 +lg 5 2 +lg 2 2 +2+1 = 3 2 +2(lg5+lg2)+3 = 3 2 +5 = 13 2 .故答案为 13 2 .

log3 根号27+lg25+lg4+7的log2幂+(-9.8)º = 3/2 + lg100 + 7^0.3010 +1 = 3/2 + 2 + 1.8 +1 = 6.3

(log5√2×log4981) ÷(log251/3×log74∧3) =[1/2 lg2×4 lg3/( lg5×2 lg7)]/[- lg3×6 lg2/(2 lg5×lg7)] =( lg2× lg3/ lg5× lg7)/(-3 lg2× lg3/ lg5×lg7) =-1/3

c

log2(3)=a, log3(7)=b log12(56)=log2(7*2³)/log2(3*2²)=[log2(7)+log2(3)]/[log2(3)+2)] =[log3(7)/log3(2)+3]/[a+2] =[ab+3]/[a+2]

网站首页 | 网站地图
All rights reserved Powered by www.dgzm.net
copyright ©right 2010-2021。
内容来自网络,如有侵犯请联系客服。zhit325@qq.com