5.设集合U={1,2,3,4,5}为全集,A={1,2,3},B={2,5},则(∁UB)∩A=( )
| A. | {2} | B. | {2,3} | C. | {3} | D. | {1,3} |
3.设f(x)=x3+ax2+bx+1的导数f'(x)满足f'(1)=2a,f'(2)=-b,其中常数a,b∈R.
(Ⅰ)求曲线y=f(x);
(Ⅱ) 设g(x)=f'(x)e-x,求函数g(x)的极值.
(Ⅰ)求曲线y=f(x);
(Ⅱ) 设g(x)=f'(x)e-x,求函数g(x)的极值.
1.函数$f(x)=\left\{\begin{array}{l}{x^2}+1,x≥0\\ 1,{\;}^{\;}{\;}^{\;}x<0\end{array}\right.$的值域为[1,+∞).
20.已知椭圆$\frac{{x}^{2}}{{a}^{2}}$+$\frac{{y}^{2}}{{b}^{2}}$=1(a>b>0)的左、右焦点分别为F1,F2,过F1且与x轴垂直的直线交椭圆于A,B两点,直线AF2与椭圆的另一个交点为C,若$\overrightarrow{A{F}_{2}}$=2$\overrightarrow{{F}_{2}C}$,则椭圆的离心率为( )
| A. | $\frac{\sqrt{5}}{5}$ | B. | $\frac{\sqrt{3}}{3}$ | C. | $\frac{\sqrt{10}}{5}$ | D. | $\frac{3\sqrt{3}}{10}$ |
19.函数y=sin2x-$\sqrt{3}$cos2x的图象的一条对称轴方程为( )
| A. | x=$\frac{π}{12}$ | B. | x=-$\frac{π}{12}$ | C. | x=$\frac{π}{6}$ | D. | x=-$\frac{π}{6}$ |
18.已知不等式组$\left\{\begin{array}{l}{2x+y-3≤0}\\{x-y+2≥0}\\{2x-3y-3≤0}\end{array}\right.$表示的平面区域为D,P(x,y)为D上一点,则|x+4|+|y+3|的最大值为( )
0 234629 234637 234643 234647 234653 234655 234659 234665 234667 234673 234679 234683 234685 234689 234695 234697 234703 234707 234709 234713 234715 234719 234721 234723 234724 234725 234727 234728 234729 234731 234733 234737 234739 234743 234745 234749 234755 234757 234763 234767 234769 234773 234779 234785 234787 234793 234797 234799 234805 234809 234815 234823 266669
| A. | $\frac{17}{2}$ | B. | 9 | C. | $\frac{29}{3}$ | D. | 10 |