5.设双曲线的渐近线方程是y=±3x,则其离心率是( )
| A. | $\sqrt{10}$或$\frac{\sqrt{10}}{3}$ | B. | $\sqrt{10}$ | C. | $\sqrt{5}$ | D. | $\sqrt{5}$或$\frac{\sqrt{5}}{2}$ |
2.O为△ABC内一点,且2$\overrightarrow{OA}$+$\overrightarrow{OB}$+$\overrightarrow{OC}$=$\overrightarrow{0}$,$\overrightarrow{AD}$=t$\overrightarrow{AC}$,若B,O,D三点共线,则t的值为( )
| A. | $\frac{1}{4}$ | B. | $\frac{1}{3}$ | C. | $\frac{1}{2}$ | D. | $\frac{2}{3}$ |
17.偶函数y=f(x)在区间[0,4]上单调递增,则有( )
| A. | f(-1)>f($\frac{π}{3}$)>f(-π) | B. | f($\frac{π}{3}$)>f(-1)>f(-π) | C. | f(-π)>f($\frac{π}{3}$)>f(-1) | D. | f(-1)>f(-π)>f($\frac{π}{3}$) |
16.sin$\frac{π}{6}$=( )
0 233101 233109 233115 233119 233125 233127 233131 233137 233139 233145 233151 233155 233157 233161 233167 233169 233175 233179 233181 233185 233187 233191 233193 233195 233196 233197 233199 233200 233201 233203 233205 233209 233211 233215 233217 233221 233227 233229 233235 233239 233241 233245 233251 233257 233259 233265 233269 233271 233277 233281 233287 233295 266669
| A. | $\frac{\sqrt{2}}{2}$ | B. | $\frac{\sqrt{3}}{3}$ | C. | $\frac{1}{2}$ | D. | $\sqrt{3}$ |