9.设集合A={x|x3-2x2-x+2=0},下列哪个元素不属于集合A( )
| A. | 1 | B. | -1 | C. | 2 | D. | -2 |
7.已知f'(x)为f(x)的导函数,若f(x)=ln$\frac{x}{2}$,且b$\int_1^b$$\frac{1}{x^3}$dx=2f'(a)+$\frac{1}{2}b}$-1,则a+b的最小值为( )
| A. | $4\sqrt{2}$ | B. | $2\sqrt{2}$ | C. | $\frac{9}{2}$ | D. | $\frac{9}{2}+2\sqrt{2}$ |
1.函数f(x)=x+$\frac{4}{x-3}$,x∈(3,+∞)的最小值为( )
| A. | 3 | B. | 4 | C. | 6 | D. | 7 |
20.若b<0,且3b+3-b=$\sqrt{13}$,则3b-3-b等于( )
0 234554 234562 234568 234572 234578 234580 234584 234590 234592 234598 234604 234608 234610 234614 234620 234622 234628 234632 234634 234638 234640 234644 234646 234648 234649 234650 234652 234653 234654 234656 234658 234662 234664 234668 234670 234674 234680 234682 234688 234692 234694 234698 234704 234710 234712 234718 234722 234724 234730 234734 234740 234748 266669
| A. | ±3 | B. | -2 | C. | -3 | D. | 9 |