已知向aa=(x,2),b=(1,y),其中x>0,y>0.若a•b=4,则1x 发布时间:2017-05-09 07:22 │ 来源:www.tikuol.com 题型:选择题 问题: 已知向aa=(x,2),b=(1,y),其中x>0,y>0.若a•b=4,则1x+2y的最小值为( )A.32B.2C.94D.22
题型:选择题 给图选择对应的对话。( ) 1. A. — What's this? — It's a desk. ( ) 2. B. — What's this? — It's a notebook.( ) 3. C. — Where do you sit? — I sit beside Jenny.( ) 4. D. — How many rulers? — Three.( ) 5. E. — Thank you! — You're welcome. 查看答案