9.已知x2+2mx+16是完全平方式,则m的值是( )
| A. | ±4 | B. | 4 | C. | -4 | D. | ±8 |
8.
如图一次函数y=kx+b的图象与y轴交于点(0,1),与x轴交于点(1,0),则关于x的不等式kx+b>1的解集是( )
| A. | x>0 | B. | x<0 | C. | x>1 | D. | x<1 |
7.下列多项式中,能用平方差公式分解因式的是( )
| A. | x2+16y2 | B. | x4-y3 | C. | -9x2+49y2 | D. | x2+1 |
6.下列运算正确的是( )
0 309603 309611 309617 309621 309627 309629 309633 309639 309641 309647 309653 309657 309659 309663 309669 309671 309677 309681 309683 309687 309689 309693 309695 309697 309698 309699 309701 309702 309703 309705 309707 309711 309713 309717 309719 309723 309729 309731 309737 309741 309743 309747 309753 309759 309761 309767 309771 309773 309779 309783 309789 309797 366461
| A. | x3•x3=2x6 | B. | (x3)2=x6 | C. | (-2x2)2=-4x4 | D. | x5÷x=x5 |