问题
解答题
在抛物线y=x2上求一点,使它到直线x-y-2=0的距离最短,并求此距离.
答案
最短距离为
.
设（x0,x02）为抛物线上任一点，则
d=
=
≥
.
当x0=
时，即抛物线上点（，
）到直线x-y-2=0的距离最短，最短距离为.
搜题请搜索小程序“爱下问搜题”
在抛物线y=x2上求一点,使它到直线x-y-2=0的距离最短,并求此距离.
最短距离为.
设（x0,x02）为抛物线上任一点，则
d=
=
≥.
当x0=时，即抛物线上点（，）到直线x-y-2=0的距离最短，最短距离为.
Birthdays are strange things. The more you have, the more you try and pretend they don’t matter, and the more 小题1: . I’m not really sure why they think so. It’s true that you are getting older, but as 小题2: , “Who isn’t getting older every day?” The problem may be that a birthday reminds people of all the things 小题3: , but have not. I certainly understand that feeling, though I think 小题4: that I most want to do — a kind of personal re-ordering (重新排序) of the to-do list. What makes you depressed(郁闷) on your birthday is that you realize your re-ordered to-do list is exactly the same as it was last year. That makes you feel 小题5: , and not been anywhere. I have not had that experience this year. I look back at where I was last year and find things have changed since then. |