5.在抛物线y=x2-6x+c上有三个点,A(-1,y1),B(2,y2),C(3+$\sqrt{2}$,y3)三点,则y1,y2,y3的大小关系是( )
| A. | y1>y2>y3 | B. | y1<y2<y3 | C. | y1>y3>y2 | D. | 不确定 |
4.已知关于x的方程kx2-3x+2=0有实数根,则k的取值范围是( )
0 297298 297306 297312 297316 297322 297324 297328 297334 297336 297342 297348 297352 297354 297358 297364 297366 297372 297376 297378 297382 297384 297388 297390 297392 297393 297394 297396 297397 297398 297400 297402 297406 297408 297412 297414 297418 297424 297426 297432 297436 297438 297442 297448 297454 297456 297462 297466 297468 297474 297478 297484 297492 366461
| A. | k$≤\frac{9}{8}$ | B. | k$>\frac{9}{8}$ | C. | k$≤\frac{9}{8}$且k≠0 | D. | k$<\frac{9}{8}$且k≠0 |