10.化简y=$\frac{2sin2α}{1+cos2α}$( )
| A. | tanα | B. | tan2α | C. | 2tanα | D. | 2tan2α |
4.
如图在复平面上,一个正方形的三个顶点对应的复数分别是1+2i,-2+i,0,那么这个正方形的第四个顶点对应的复数为( )
| A. | 3+i | B. | -1+3i | C. | 1-3i | D. | 3-i |
3.在极坐标系中,点M(1,0)关于极点的对称点为( )
| A. | (1,0) | B. | (-1,π) | C. | (1,π) | D. | (1,2π) |
2.在同一平面直角坐标系中,点A($\frac{1}{3}$,-2)经过伸缩变换φ:$\left\{\begin{array}{l}{x′=3x}\\{2y′=y}\end{array}\right.$所得的点A′的坐标为( )
0 237707 237715 237721 237725 237731 237733 237737 237743 237745 237751 237757 237761 237763 237767 237773 237775 237781 237785 237787 237791 237793 237797 237799 237801 237802 237803 237805 237806 237807 237809 237811 237815 237817 237821 237823 237827 237833 237835 237841 237845 237847 237851 237857 237863 237865 237871 237875 237877 237883 237887 237893 237901 266669
| A. | (1,-1) | B. | (1,-4) | C. | $({\frac{1}{9},-4})$ | D. | (9,-1) |