11.已知点P(2-a,3a+6)到两坐标轴的距离相等,则点P的坐标为( )
| A. | (3,3)或(6,-6) | B. | (3,-3)或 (6,-6) | C. | (3,3) | D. | (3,-3) |
10.已知二次函数y=ax2+bx+c与自变量x的部分对应值如表:
现给出下列说法:
①该函数开口向下.
②该函数图象的对称轴为过点(1,0)且平行于y轴的直线.
③当x=2时,y=3.
④方程ax2+bx+c=-2的正根在3与4之间.
其中正确的说法为①③④.(只需写出序号)
0 284314 284322 284328 284332 284338 284340 284344 284350 284352 284358 284364 284368 284370 284374 284380 284382 284388 284392 284394 284398 284400 284404 284406 284408 284409 284410 284412 284413 284414 284416 284418 284422 284424 284428 284430 284434 284440 284442 284448 284452 284454 284458 284464 284470 284472 284478 284482 284484 284490 284494 284500 284508 366461
| x | … | -1 | 0 | 1 | 3 | … |
| y | … | -3 | 1 | 3 | 1 | … |
①该函数开口向下.
②该函数图象的对称轴为过点(1,0)且平行于y轴的直线.
③当x=2时,y=3.
④方程ax2+bx+c=-2的正根在3与4之间.
其中正确的说法为①③④.(只需写出序号)