比较1.513.1、23.1、213.1的大小关系是（）A.23.1<213.1<1.513.1B.1.513.1<23.1<213.1C.1.513.1<213.1<23.1D.213.1<1.513.1<23.1

Question

比较1.5

(1)/(3.1)、2^3.1、2(1)/(3.1)的大小关系是（　　）

A. 2^3.1<2

(1)/(3.1)<1.5(1)/(3.1)

B. 1.5

(1)/(3.1)<2^3.1<2(1)/(3.1)

C. 1.5

(1)/(3.1)<2(1)/(3.1)<2^3.1

D. 2

(1)/(3.1)<1.5(1)/(3.1)<2^3.1

Answer 1

由于函数y=2^x为增函数可得，23.1>2(1)/(3.1)
而由幂函数的性质可得，1.5(1)/(3.1)<2(1)/(3.1)
∴1.5(1)/(3.1)<2(1)/(3.1)<23.1
故选C．