已知点P是双曲线x2a2-y2b2=1(a>0,b>0)和圆x2+y2=a2+b 发布时间:2017-04-30 01:05 │ 来源:www.tikuol.com 题型:选择题 问题: 已知点P是双曲线x2a2-y2b2=1(a>0,b>0)和圆x2+y2=a2+b2的一个交点,F1,F2是该双曲线的两个焦点,∠PF2F1=2∠PF1F2,则该双曲线的离心率为( )A.12B.3+12C.2D.3+1
题型:选择题 Talks between the two countries, _____ is reported in the newspapers, are making progress. [ ]A. it B. as C. what D. which 查看答案