9.直角坐标系中,点$(1,-\sqrt{3})$的极坐标可以是( )
| A. | $(2,\frac{4π}{3})$ | B. | $(2,\frac{5π}{3})$ | C. | $(2,\frac{5π}{6})$ | D. | $(2,\frac{11π}{6})$ |
7.已知命题p:关于x的函数y=x2-3ax+4在[1,+∞)上是增函数,命题q:函数y=(2a-1)x为减函数,若“p且q”为真命题,则实数a的取值范围是( )
0 252752 252760 252766 252770 252776 252778 252782 252788 252790 252796 252802 252806 252808 252812 252818 252820 252826 252830 252832 252836 252838 252842 252844 252846 252847 252848 252850 252851 252852 252854 252856 252860 252862 252866 252868 252872 252878 252880 252886 252890 252892 252896 252902 252908 252910 252916 252920 252922 252928 252932 252938 252946 266669
| A. | (-∞,$\frac{2}{3}$] | B. | (0,$\frac{1}{2}$) | C. | ($\frac{1}{2}$,$\frac{2}{3}$] | D. | ($\frac{1}{2}$,1) |