1.若$a = \frac{1011}{506}\text{e}^{\frac{1009}{1014}}$,$b = \frac{1009}{507}\text{e}^{\frac{1011}{1012}}$,$c = \frac{2016}{507}$,$\text{e}$是自然对数的底数,则( )
A.$c > a > b$ B.$b > a > c$ C.$c > b > a$ D.$a > b > c$
解:设$f(x) = \text{e}^{x} - \text{e}x$,$x \in (1, + \infty)$,则$f'(x) = \text{e}^{x} - \text{e} > 0$在$(1, + \infty)$上恒成立,所以$f(x)$在$(1, + \infty)$上单调递增,则$f(x) > f(1) = 0$,所以$\text{e}^{x} > \text{e}x$,
所以$b = \frac{1009}{507}\text{e}^{\frac{1011}{1012}} > \frac{1009}{507} \times \text{e} \times \frac{1011}{1012} > \frac{1009}{507} \times 2 = \frac{2018}{507} > \frac{2016}{507} = c$,
设$h(x) = \frac{2x}{\text{e}^{x}},x \in (0,1)$,则$h'(x) = \frac{2(1 - x)}{\text{e}^{x}} > 0$,所以$h(x)$在$(0,1)$上单调递增,则$h(x) > h(0) = 0$,
又$0 < \frac{1009}{1014} < \frac{1009 + 2}{1014 - 2} = \frac{1011}{1012} < 1$,则$h\left( \frac{1009}{1014} \right) < h\left( \frac{1011}{1012} \right)$,即$\frac{\frac{1009}{507}}{\text{e}^{\frac{1009}{1014}}} < \frac{\frac{1011}{506}}{\text{e}^{\frac{1011}{1012}}}$,则$\frac{1009}{507}\text{e}^{\frac{1011}{1012}} < \frac{1011}{506}\text{e}^{\frac{1009}{1014}}$,故$b < a$,综上可得:$a > b > c$.