13.
如图,在等腰直角△ABC中,∠BAC=90°,AB=AC,BC=4$\sqrt{2}$,点D是AC上一动点,连接BD,以AD为直径的圆交BD于点E,则线段CE长度的最小值是( )
| A. | 2 | B. | 4 | C. | $2\sqrt{2}-2$ | D. | $2\sqrt{5}-2$ |
8.要使(x2+ax+1)(-6x3)的展开式中不含x4项,则a应等于( )
0 295436 295444 295450 295454 295460 295462 295466 295472 295474 295480 295486 295490 295492 295496 295502 295504 295510 295514 295516 295520 295522 295526 295528 295530 295531 295532 295534 295535 295536 295538 295540 295544 295546 295550 295552 295556 295562 295564 295570 295574 295576 295580 295586 295592 295594 295600 295604 295606 295612 295616 295622 295630 366461
| A. | 6 | B. | -1 | C. | $\frac{1}{6}$ | D. | 0 |