11.计算$\frac{2x}{{x}^{2}-1}$-$\frac{1}{x-1}$的结果是( )
| A. | x-1 | B. | $\frac{1}{x+1}$ | C. | $\frac{2}{x+1}$ | D. | 2x+1 |
7.
如图,ABCD为正方形,O为对角线AC、BD的交点,则△COD绕点O经过下列哪种旋转可以得到△DOA( )
| A. | 顺时针旋转90° | B. | 顺时针旋转45° | C. | 逆时针旋转90° | D. | 逆时针旋转45° |
6.
如图,正三角形ABC内接于圆O,AD⊥BC于点D交圆于点E,动点P在优弧BAC上,且不与点B,点C重合,则∠BPE等于( )
0 284004 284012 284018 284022 284028 284030 284034 284040 284042 284048 284054 284058 284060 284064 284070 284072 284078 284082 284084 284088 284090 284094 284096 284098 284099 284100 284102 284103 284104 284106 284108 284112 284114 284118 284120 284124 284130 284132 284138 284142 284144 284148 284154 284160 284162 284168 284172 284174 284180 284184 284190 284198 366461
| A. | 30° | B. | 45° | C. | 60° | D. | 90° |