英语周报2020—2021八年级第7期答案

x=1+yt22.解:(1)直线l的参数方程为(t为参y=2+消去t得,直线l的普通方程为x-y+1=0;(2分)由p=1+sm7得,p+p2snb=2,将p2=x2+y2,psin0=y代人得曲线C的直角坐标方程为+y2(5分)(2)将直线l的参数方程代入曲线Cy=2+t整理得3t2+10√2t+14=0,7分记A,B两点对应的参数分别为t1,t则t1+t2√2,t1t214故p+PPA|+|PB|_|t+t2152I PAlPB41t2(10分

书面表达One possible versionDear PeterI'm writing to invite you to see the Chinese Painting Exhibition to be held in our city.The exhibition will start at 8: 30 am on Saturday and last till 5: 00 pm on Sunday in the city museum It'ssaid that a large number of Chinese paintings, some of which are original works by famous painters like ZhangDaqian and Qi Baishi, will be on display. Besides, there will be various souvenirs to be sold. I know you re veryinterested in traditional Chinese culture, so I can t wait to tell you the news and hope we can go together.Looking forward to your reply.You

以上就是英语周报2020—2021八年级第7期答案，更多英语周报答案请关注本网站。