问题
选择题
三个数20110.99,0.992011,log0.992011的大小关系为( )
A.log0.992011<0.992011<20110.99
B.log0.992011<20110.99<0.992011
C.0.992011<log0.992011<20110.99
D.0.992011<20110.99<log0.992011
答案
设f(x)=2011x,g(x)=0.99x,h(x)=log0.99x
则f(x)单调递增,g(x)单调递减,h(x)单调递减
∴f(0.99)=20110.99>20110=1
0<g(2011)=0.992011<0.990=1
h(2011)=log0.992011<log0.991=0
即20110.99>1,0<0.992011<1,log0.992011<0
∴log0.992011<0.992011<20110.99
故选A