15.如(x2+mx+1)(x3-3x+1)乘积中不含x4项,则m的值为( )
0 284344 284352 284358 284362 284368 284370 284374 284380 284382 284388 284394 284398 284400 284404 284410 284412 284418 284422 284424 284428 284430 284434 284436 284438 284439 284440 284442 284443 284444 284446 284448 284452 284454 284458 284460 284464 284470 284472 284478 284482 284484 284488 284494 284500 284502 284508 284512 284514 284520 284524 284530 284538 366461
| A. | -3 | B. | 3 | C. | 0 | D. | 1 |