4.曲线$y=\frac{sinx}{x}$在点M(π,0)处的切线方程为( )
| A. | y=$\frac{1}{π}x-1$ | B. | y=$-\frac{1}{π}x+1$ | C. | y=$\frac{1}{π}x+1$ | D. | y=$-\frac{1}{π}x-1$ |
3.有3个旅游团分别从奇台县江布拉克、古城公园、靖宁公园、恐龙沟、魔鬼城5个风景点中选择一处游览,不同的选法有( )
| A. | 15 | B. | 243 | C. | 125 | D. | 60 |
2.复数m(3+i)-(2+i)在复平面内对应的点在第四象限,则m的取值范围是( )
| A. | .$[{\frac{2}{3},1})$ | B. | .$({\frac{2}{3},1})$ | C. | .$({\frac{2}{3},1}]$ | D. | $[{\frac{2}{3},1}]$ |
1.复数${({\frac{1}{2}+\frac{{\sqrt{3}}}{2}i})^3}$的共轭复数是( )
| A. | -i | B. | i | C. | -1 | D. | 1 |
18.下列可以作为直线2x-y+1=0的参数方程的是( )
0 240216 240224 240230 240234 240240 240242 240246 240252 240254 240260 240266 240270 240272 240276 240282 240284 240290 240294 240296 240300 240302 240306 240308 240310 240311 240312 240314 240315 240316 240318 240320 240324 240326 240330 240332 240336 240342 240344 240350 240354 240356 240360 240366 240372 240374 240380 240384 240386 240392 240396 240402 240410 266669
| A. | $\left\{\begin{array}{l}x=1+t\\ y=3+t\end{array}\right.(t为参数)$ | B. | $\left\{\begin{array}{l}x=1-t\\ y=5-2t\end{array}\right.(t为参数)$ | ||
| C. | $\left\{\begin{array}{l}x=1-t\\ y=3-2t\end{array}\right.(t为参数)$ | D. | $\left\{\begin{array}{l}x=2+\frac{{2\sqrt{5}}}{5}t\\ y=5+\frac{{\sqrt{5}}}{5}t\end{array}\right.(t为参数)$ |