9.已知抛物线y2=4px(p>0)上一点M到该抛物线焦点F的距离|MF|=3p,则直线MF的斜率为( )
| A. | ±2$\sqrt{2}$ | B. | ±1 | C. | ±$\sqrt{3}$ | D. | ±$\frac{\sqrt{3}}{3}$ |
8.已知直线x-$\sqrt{2}$y-$\sqrt{2}$=0经过椭圆C:$\frac{{x}^{2}}{{a}^{2}}$+$\frac{{y}^{2}}{{b}^{2}}$=1(a>b>0)的焦点和顶点,则椭圆C的离心率为( )
| A. | $\sqrt{2}$ | B. | $\frac{\sqrt{6}}{3}$ | C. | $\frac{\sqrt{3}}{3}$ | D. | $\frac{\sqrt{2}}{3}$ |
7.已知实数x,y满足$\left\{\begin{array}{l}{x-y≤0}\\{x+y+2≥0}\\{x-2y+2≥0}\end{array}\right.$,则x+2y的取值范围为( )
| A. | [-3,2] | B. | [-2,6] | C. | [-3,6] | D. | [2,6] |
6.抛物线y2=4x的焦点到双曲线$\frac{{x}^{2}}{4}$-y2=1的渐近线的距离为( )
| A. | $\frac{1}{5}$ | B. | $\frac{\sqrt{5}}{5}$ | C. | $\frac{2}{5}$ | D. | $\frac{2\sqrt{5}}{5}$ |
3.全组有8个男同学,4个女同学,现选出5个代表,最多有2个女同学当选的选法种数是( )
| A. | 672 | B. | 616 | C. | 336 | D. | 280 |
2.在二项式(2x2+$\frac{1}{x}$)6的展开式中,常数项是( )
0 240510 240518 240524 240528 240534 240536 240540 240546 240548 240554 240560 240564 240566 240570 240576 240578 240584 240588 240590 240594 240596 240600 240602 240604 240605 240606 240608 240609 240610 240612 240614 240618 240620 240624 240626 240630 240636 240638 240644 240648 240650 240654 240660 240666 240668 240674 240678 240680 240686 240690 240696 240704 266669
| A. | 50 | B. | 60 | C. | 45 | D. | 80 |