设A(x1,y1),B(x2,y2),(x1>橘行衫带纤x2),可得2x1?12=12?2x2?2x1+2x2=1,利圆腔用均值不等式1>2 2x1+x2?2 x1+x2<14 ∴x1+x2<?2, B.