5.椭圆$\frac{x^2}{3}+\frac{y^2}{2}=1$上一点P到左焦点的距离为$\frac{{\sqrt{3}}}{2}$,则P到右准线的距离为( )
| A. | $\frac{\sqrt{3}}{3}$ | B. | $\frac{5\sqrt{5}}{10}$ | C. | $\frac{9}{2}$ | D. | $\frac{3}{2}$ |
4.某几何体三视图如图所示,则该几何体的表面积为( )

| A. | (9+$\sqrt{5}$)π | B. | (9+2$\sqrt{5}$)π | C. | (10+$\sqrt{5}$)π | D. | (10+2$\sqrt{5}$)π |
19.若x,y满足约束条件$\left\{\begin{array}{l}{x+y>1}\\{x-y≥-1}\\{2x-y≤2}\end{array}\right.$,且目标函数z=ax+2y仅在点(1,0)处取得最小值,则a的取值范围是( )
| A. | (-1,2) | B. | (-4,2) | C. | (-4,0) | D. | (-4,2) |
18.函数f(x)=3x-4x3,(x∈[0,1])的最大值是( )
| A. | $\frac{1}{2}$ | B. | -1 | C. | 0 | D. | 1 |
17.命题“?x0∈R,x03-x02+1>0”的否定是( )
0 237161 237169 237175 237179 237185 237187 237191 237197 237199 237205 237211 237215 237217 237221 237227 237229 237235 237239 237241 237245 237247 237251 237253 237255 237256 237257 237259 237260 237261 237263 237265 237269 237271 237275 237277 237281 237287 237289 237295 237299 237301 237305 237311 237317 237319 237325 237329 237331 237337 237341 237347 237355 266669
| A. | ?x0∈R,x${\;}_{0}^{3}$-x${\;}_{0}^{2}$+1<0 | B. | ?x∈R,x3-x2+1≤0 | ||
| C. | ?x0∈R,x${\;}_{0}^{3}$-x${\;}_{0}^{2}$+1≤0 | D. | ?x∈R,x3-x2+1>0 |