11.在比例尺为1:5000的地图上,量得甲、乙两地的距离为25cm,则甲、乙两地的实际距离是( )
| A. | 1 250 km | B. | 125 km | C. | 12.5 km | D. | 1.25 km |
10.下列方程中两根之和为-1的是( )
| A. | x2-x+5=0 | B. | x2-x-5=0 | C. | x2+x+5=0 | D. | x2+x-5=0 |
9.关于x的一元二次方程(m-1)x2+6x+m2-1=0有一个根是0,则m取值为( )
| A. | 1 | B. | -1 | C. | ±1 | D. | 0 |
8.下列计算结果正确的是( )
| A. | 6x6÷2x3=3x2 | B. | x2+x2=x4 | ||
| C. | -2x2y(x-y)=-2x3y+2x2y2 | D. | (-3xy2)3=-9x3y6 |
7.在$\frac{1}{3}$,-2,π,$\sqrt{7}$这四个数中,无理数的个数是( )
| A. | 1个 | B. | 2个 | C. | 3个 | D. | 4个 |
6.若|a|=8,则$\frac{a+8}{2}$的值为( )
| A. | 0 | B. | 0或8 | C. | 4 | D. | -8或8 |
5.下列四个数中,最小的是( )
0 287710 287718 287724 287728 287734 287736 287740 287746 287748 287754 287760 287764 287766 287770 287776 287778 287784 287788 287790 287794 287796 287800 287802 287804 287805 287806 287808 287809 287810 287812 287814 287818 287820 287824 287826 287830 287836 287838 287844 287848 287850 287854 287860 287866 287868 287874 287878 287880 287886 287890 287896 287904 366461
| A. | 0 | B. | -2 | C. | -8 | D. | 1 |