7.一次函数y=kx-k的图象大致为( )
| A. | B. | C. | D. |
5.
如图,∠BAC=60°,AD是∠BAC的角平分线,点D在AD上,过点D作DE∥AB交AC于点E.若DE=2,则点D到AB的距离为( )
| A. | 1 | B. | $\sqrt{3}$ | C. | 2 | D. | 2$\sqrt{3}$ |
3.对于二项方程axn+b=0(a≠0,b≠0),当n为偶数时,已知方程无实数根,那么ab一定( )
| A. | ab<0 | B. | ab≤0 | C. | ab>0 | D. | ab≥0 |
20.若a>b,且c为任意有理数,则下列不等式正确的是( )
0 295585 295593 295599 295603 295609 295611 295615 295621 295623 295629 295635 295639 295641 295645 295651 295653 295659 295663 295665 295669 295671 295675 295677 295679 295680 295681 295683 295684 295685 295687 295689 295693 295695 295699 295701 295705 295711 295713 295719 295723 295725 295729 295735 295741 295743 295749 295753 295755 295761 295765 295771 295779 366461
| A. | ac>bc | B. | ac<bc | C. | ac2>bc2 | D. | a+c>b+c |