20.在反比例函数y=$\frac{1-3k}{x}$的图象上有两点A(x1,y1),B(x2,y2),当0<x1<x2时,有y1>y2,则k的取值范围是( )
| A. | k$>\frac{1}{3}$ | B. | k$<\frac{1}{3}$ | C. | k$≥\frac{1}{3}$ | D. | k$≤\frac{1}{3}$ |
15.
如图,在平面直角坐标系中,Rt△OAB的顶点A、B的坐标分别是(2,0),(2,4),将△OAB绕点O逆时针方向旋转90°,得到△OA′B′,函数y=$\frac{k}{x}$(x<0)的图象过A′B′的中点C,则k的值为( )
0 284440 284448 284454 284458 284464 284466 284470 284476 284478 284484 284490 284494 284496 284500 284506 284508 284514 284518 284520 284524 284526 284530 284532 284534 284535 284536 284538 284539 284540 284542 284544 284548 284550 284554 284556 284560 284566 284568 284574 284578 284580 284584 284590 284596 284598 284604 284608 284610 284616 284620 284626 284634 366461
| A. | 4 | B. | -4 | C. | 8 | D. | -8 |