14.若变量x,y满足约束条件$\left\{\begin{array}{l}{y≤1}\\{x+y≥0}\\{x-y-2≥0}\\{\;}\end{array}\right.$,则z=x-2y的最小值是( )
| A. | 3 | B. | 1 | C. | -3 | D. | 不存在 |
13.若将函数f(x)=sin(2x+$\frac{π}{3}$)的图象向右平移φ个单位,所得图象关于y轴对称,则φ的最小正值是( )
| A. | $\frac{π}{6}$ | B. | $\frac{π}{4}$ | C. | $\frac{5π}{12}$ | D. | $\frac{11π}{12}$ |
12.已知命题p:?x∈R,x+$\frac{4}{x}$≥4;命题q:?x0∈(0,∞),log2x0=$\frac{1}{2}$,则下列命题中为真命题的是( )
| A. | p∧q | B. | p∨(¬q) | C. | (¬p)∧q | D. | (¬p)∧(¬q) |
11.下列函数中,满足f(-x)+f(x)=0的单调递增函数是( )
| A. | f(x)=x3 | B. | f(x)=-x-1 | C. | f(x)=log2x | D. | f(x)=2x |
10.已知复数z=i(1-i),则|z|=( )
| A. | 2 | B. | $\sqrt{2}$ | C. | 5 | D. | $\sqrt{5}$ |
9.
若全集U=R,A={0,1,2,3},B={2,3,4,5},则Venn图中阴影部分表示的集合为( )
| A. | {0,1} | B. | {2,3} | C. | {4,5} | D. | {0,1,4,5} |
8.已知△ABC的三个顶点坐标分别为A(-2,3),B(-2,-1),C(6,-1),以原点为圆心的圆与此三角形有唯一的公共点,则圆的方程为( )
| A. | x2+y2=1 | B. | x2+y2=4 | ||
| C. | x2+y2=$\frac{16}{5}$ | D. | x2+y2=1或x2+y2=37 |
7.当实数x,y满足不等式组$\left\{\begin{array}{l}{x+y≥1}\\{y≤1}\\{x-y≤1}\end{array}\right.$,恒有ax+y≤3,则实数a的取值范围是( )
| A. | (-∞,1] | B. | (-∞,-1] | C. | [-1,+∞) | D. | [1,+∞) |
6.若函数f(x)=sin(ωx+$\frac{π}{6}$)(ω>0),满足f(0)=f($\frac{π}{3}$),且函数在[0,$\frac{π}{2}$]上有且只有一个零点,则f(x)的最小正周期为( )
0 227748 227756 227762 227766 227772 227774 227778 227784 227786 227792 227798 227802 227804 227808 227814 227816 227822 227826 227828 227832 227834 227838 227840 227842 227843 227844 227846 227847 227848 227850 227852 227856 227858 227862 227864 227868 227874 227876 227882 227886 227888 227892 227898 227904 227906 227912 227916 227918 227924 227928 227934 227942 266669
| A. | $\frac{π}{2}$ | B. | π | C. | $\frac{3π}{2}$ | D. | 2π |