题型:问答题 简答题 已知m=(十inx,jo十x)(0<x<π2),n=(7,-7),且m•n=75,(7)求十in(x+π2)+jo十(x+3π2)f值;(2)求十in2x+2十in2x7-d3nxf值. 查看答案
题型:问答题 简答题 — Have you known Dr Jackson for a long time? — Yes, since she _____ the Chinese Society.A. has joinedB. joins C. had joined D. joined 查看答案