已知lg2=0.301,lg3=0.477,求(1)log(2)1000,(2)log(5)0.5,(3)log(9)8,(4)log(1/2)1/3
问题描述:
已知lg2=0.301,lg3=0.477,求(1)log(2)1000,(2)log(5)0.5,(3)log(9)8,(4)log(1/2)1/3
答
1、log(2)1000=lg1000/lg2=3/0.301=9.9667772、log(5)0.5=(lg2-1)/(1-lg2)=-13、log(9)8=lg8/lg9=3lg2/2lg3=0.9465404、log(1/2)1/3=(1-lg3)/(1-lg2)=0.523/0.699=0.748212