16.已知函数f(x)=$\left\{\begin{array}{l}{{2}^{x}(x≤0)}\\{f(x-3)(x>0)}\end{array}$,则f(2013)=( )
| A. | 2 | B. | 1 | C. | $\frac{1}{2}$ | D. | $\frac{1}{4}$ |
15.已知集合M={x|-1<x<3,x∈R},N={-1,0,1,2,3},则M∩N=( )
| A. | {-1,0,2,3} | B. | {-1,0,1,2} | C. | {0,1,2} | D. | {0,1,2,3} |
13.设f(x)是(-∞,+∞)上的减函数,则不等式f(2)<f(2x+1)的解集是( )
| A. | $(0,\frac{1}{2})$ | B. | $(-∞,\frac{1}{2})$ | C. | $(\frac{1}{2},+∞)$ | D. | $(-∞,0)∪(\frac{1}{2},+∞)$ |
12.已知函数f(x)=lnx+$\frac{1}{2}$ax2-2x有两个极值点,则a的取值范围是( )
| A. | (-∞,1) | B. | (0,2) | C. | (0,1) | D. | (0,3) |
11.下列函数中,在其定义域内既是奇函数又是减函数的是( )
| A. | y=($\frac{1}{2}$)x | B. | y=$\frac{1}{x-1}$ | C. | y=x+sinx | D. | y=-x3-x |
8.已知点P为椭圆$\frac{{x}^{2}}{16}$+$\frac{{y}^{2}}{12}$=1上的动点,EF为圆N:x2+(y-1)2=1的任一直径,求$\overrightarrow{PE}•\overrightarrow{PF}$最大值和最小值是( )
0 234537 234545 234551 234555 234561 234563 234567 234573 234575 234581 234587 234591 234593 234597 234603 234605 234611 234615 234617 234621 234623 234627 234629 234631 234632 234633 234635 234636 234637 234639 234641 234645 234647 234651 234653 234657 234663 234665 234671 234675 234677 234681 234687 234693 234695 234701 234705 234707 234713 234717 234723 234731 266669
| A. | 16,12-4$\sqrt{3}$ | B. | 17,13-4$\sqrt{3}$ | C. | 19,12-4$\sqrt{3}$ | D. | 20,13-4$\sqrt{3}$ |