6.将抛物线y=ax2-1平移后与抛物线y=a(x-1)2重合,抛物线y=ax2-1上的点A(2,3)同时平移到A′,那么点A′的坐标为( )
| A. | (3,4) | B. | (1,2) | C. | (3,2) | D. | (1,4) |
5.在Rt△ABC中,∠C=90°,如果AB=m,∠A=α,那么AC的长为( )
| A. | m•sinα | B. | m•cosα | C. | m•tanα | D. | m•cotα |
4.下列多项式中,在实数范围不能分解因式的是( )
| A. | x2+y2+2x+2y | B. | x2+y2+2xy-2 | C. | x2-y2+4x+4y | D. | x2-y2+4y-4 |
3.a${\;}^{-\frac{1}{2}}$(a>0)等于( )
0 291046 291054 291060 291064 291070 291072 291076 291082 291084 291090 291096 291100 291102 291106 291112 291114 291120 291124 291126 291130 291132 291136 291138 291140 291141 291142 291144 291145 291146 291148 291150 291154 291156 291160 291162 291166 291172 291174 291180 291184 291186 291190 291196 291202 291204 291210 291214 291216 291222 291226 291232 291240 366461
| A. | $\sqrt{a}$ | B. | -$\sqrt{a}$ | C. | $\frac{\sqrt{a}}{a}$ | D. | -$\frac{\sqrt{a}}{a}$ |