题目

(本题满分8分)直线y=―x―2与反比例函数y=的图像交于A、B两点,且与x、y轴交于C、D两点,A点的坐标为(-3,k+4).(1)求反比例函数的解析式(2)把直线AB绕着点M(―1,―1)顺时针旋转到MN,使直线MN⊥x轴,且与反比例函数的图像交于点N,求旋转角大小及线段MN的长。 答案:解:(1)将点A(-3,k+4)代入直线y=―x―2得k+4=―(―3)―2解得k=―3∴点A(―3,1)于是反比例函数的解析式为y=(2)C、D两点的坐标为(―2,0)、(0,―2)。∴在△OCD中,∠OCD=45°。所以旋转角为45°。点M、N的坐标为(―1,―1)(―1,3)∴MN的长度为4.解析:略请听下面一段材料,回答第1至第4四个小题。 1. When will the ballet performances be on? [     ]A. This week. B. Next week. C. Next month. 2. When will the man attend the performance? [     ]A. On Sunday evening. B. On Thursday evening. C. On Friday evening. 3. How much does the man pay for the tickets? [     ]A. $20. B. $10. C. $40. 4. Where are they now ? [     ]A. In a book store B. In a clothing store C. In a theatre
数学 试题推荐