16.直线l经过两点(1,$\sqrt{3}$),B(-2,2$\sqrt{3}$),则直线l的倾斜角为( )
| A. | $\frac{π}{6}$ | B. | $\frac{π}{3}$ | C. | $\frac{2π}{3}$ | D. | $\frac{5π}{6}$ |
15.△ABC是边长为2的等边三角形,已知向量$\overrightarrow{a}$,$\overrightarrow{b}$,满足$\overrightarrow{AB}$=2$\overrightarrow{a}$,$\overrightarrow{AC}$=2$\overrightarrow{a}$+$\overrightarrow{b}$,则下列结论正确的是( )
| A. | (4$\overrightarrow{a}$+$\overrightarrow{b}$)⊥$\overrightarrow{BC}$ | B. | |$\overrightarrow{b}$|=1 | C. | $\overrightarrow{a}$•$\overrightarrow{b}$=1 | D. | $\overrightarrow{a}$⊥$\overrightarrow{b}$ |
14.已知$\overrightarrow{a}$=(x,-2x),$\overrightarrow{b}$=(x-1,3)且$\overrightarrow{a}$∥$\overrightarrow{b}$,则x等于( )
| A. | -$\frac{1}{2}$ | B. | 0 | C. | -$\frac{1}{2}$或0 | D. | 0或7 |
12.已知函数f(x)=x2-2x+alnx有两个极值点x1,x2,且x1<x2,则( )
| A. | $f({x_1})<\frac{3+2ln2}{4}$ | B. | $f({x_1})<-\frac{1+2ln2}{4}$ | C. | $f({x_1})>\frac{1+2ln2}{4}$ | D. | $f({x_1})>-\frac{3+2ln2}{4}$ |
11.
如图,在矩形ABCD中,$AB=\frac{3}{2}$,BC=2,沿BD将矩形ABCD折叠,连结AC,所得三棱锥A-BCD的正视图和俯视图如图所示,则三棱锥A-BCD的体积为( )
0 233187 233195 233201 233205 233211 233213 233217 233223 233225 233231 233237 233241 233243 233247 233253 233255 233261 233265 233267 233271 233273 233277 233279 233281 233282 233283 233285 233286 233287 233289 233291 233295 233297 233301 233303 233307 233313 233315 233321 233325 233327 233331 233337 233343 233345 233351 233355 233357 233363 233367 233373 233381 266669
| A. | $\frac{6}{5}$ | B. | $\frac{3}{5}$ | C. | $\frac{4}{5}$ | D. | $\frac{12}{5}$ |