若lg2=a lg3=b则log2
来源:学生作业帮助网 编辑:作业帮 时间:2024/05/16 14:35:12
log12(5)=lg5/lg12=lg(10/2)/lg(3×4)=(lg10-lg2)/(lg4+lg3)=(lg10-lg2)/(2lg2+lg3)=(1-a)/(2a+b)log14(56)=
log89=a,log925=b,求lg22/3log2(3)=a,log3(5)=b,log2(3)=3a/2,log2(5)/log2(3)=b,log2(5)=b*log2(3)=3ab/2.l
应该有个a≠b吧,ab=1logab=lnb/lnalogba=lna/lnb因为logab=logba所以lnb/lna=lna/lnb(lnb)^2=(lna)^2lnb=lna或者lnb=-ln
log26=lg6/lg2=lg2+lg3)/lg2=(a+b)/a所以错误lg4/lg3xlg8/lg4xlgm/8=2lgm/lg3=2所以m=9希望对你有帮助学习进步O(∩_∩)O谢谢
(2a+b)/(1-a)
令a=log3(2)所以3^a=2取常用对数lg3^a=lg2alg3=lg2a=lg2÷lg3再问:3^a=2→lg3^a=lg2是在“3^a=2”两边加上lg吗?就是x1=x2等于lgx1=lgx
log(小字12)5=1/(log(小字5)12)=lg12/lg5=(2lg2+lg3)/(1-lg2)=(2a+b)/(1-a)
1.log(12)5=lg5/lg12=lg(10/2)/lg(3*2*2)=(1-lg2)/(lg3+2lg2)=(1-a)/(b+2a)2.log(14)56=log(3)56/log(3)14=
(1)(1-a)/(2a+b);(2)(3+ab)/(1+ab)
lg2=a,lg3=blg5=1-lg2=1-alog1845=lg45/lg18=(lg5+lg9)/(lg9+lg2)=(lg5+2lg3)/(lg2+2lg3)=(lg5+2b)/(a+2b)=
log以18为底45=lg45/lg18=lg(5*9)/lg(9*2)=(lg9+lg5)/(lg9+lg2)=(2lg3+lg5)/(2lg3+lg2)=(2b+lg(10/2))/(2b+a)=
还有一种方法利用对数的性质:因为log512=lg12/lg5又因为lg12=2lg2*lg3lg5=1-lg2所以lg12/lg5=(2a+b)/(1-a)即log512=(2a+b)/(1-a)
log(4)12+log(2)15=lg12/lg4+lg15/lg2=lg2*2*3/lg2*2+lg(10*3/2)/lg2=(a+a+b)/(a+a)+(1+b-a)/a=1+b/2a+1/a+
a=lg9/lg8=2lg3/3lg2所以lg3=(3alg2)/2b=lg3/lg5lg3=blg5=b(1-lg2)所以(3alg2)/2=b(1-lg2)(3a/2)lg2=b-blg2(3a/
㏒44^3+㏒10^2=3+2=5,2lg2+lg25-10=lg(4×25÷10)=1.
log(5)12=(lg3+lg4)/lg5=(2lg2+lg3)/(1-lg2)=(2a+b)/(1-a)
(1)因为log(3)5=a,5的b次=7即:log(3)5=a,log(5)7=b,log(3)7=a/b所以log(63)105=log(63)3x7x5=log(63)3+log(63)7+lo
log(8)9=lg9/lg8=2lg3/3lg2=a,lg2=2lg3/3a.log(3)5=lg5/lg3=b,lg3=lg5/b.lg5+lg2=lg10=1所以,lg2=2/(3ab+2)再问
2/(2+3ab)lg2=1/log(2)(10)=1/(log(2)(2)+log(2)(5))=1/{1+〖log(3)(5)/log(3)(2)〗}=1/{1+〖log(3)(5)log(2)(
log(6,16)=lg16/1g6=4lg2/(lg2+lg3)=4a/(a+b)