已知向量
（1）求实数a的值； （2）把函数y=f（x）的图象向右平移
|
（1）f（x）=1+cosωx+a+
sinωx=2sin（ωx+3
）+a+1．π 6
因为函数f（x）在R上的最大值为2，
所以3+a=2，故a=-1．
（2）由（1）知：f（x）=2sin（ωx+
），π 6
把函数f（x）=2sin（ωx+
）的图象向右平移π 6
个单位，可得函数π 6ω
y=g（x）=2sinωx．
又∵y=g（x）在[0，
]上为增函数，π 4
∴g（x）的周期T=
≥π，即ω≤2，2π ω
∴ω的最大值为2．
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| There are thousands of people across the United States without any food or shelter (住所)．Every Saturday or Sunday night,my family and I go out and__1__the homeless people in the city. There is one__2__thing I like to mention here.Before we begin our__3__,my family and I do not eat.We do this__4__we know how it feels to be hungry.We all get together in the kitchen and__5__the food.We then__6__ the food for 30 or more people.I like to write a special__7__on the bags like"God loves you"． A lot of people__8__homeless people.Not all homeless people are bad people.Some are really__9__.Many people hate them__10__no good reason.In the beginning,when my family and I went out on the street,we had to__11__their trust.Later,as they__12__us every week,they started to trust us.We__13__ know some of their names.We all have to keep in mind that they also have__14__.Some of them shake our hands for giving them food,and__15__us.Some of them do really funny dances because they are __16__. We have become__17__close to a man named Tony and his wife.After meeting with them several times,he has told us a lot about his__18__.He graduated from college and has a PHD.He used to teach French and Spanish. After we get done feeding the homeless,it makes me__19__what I have at home.Sometimes it makes me sad,and makes my mom cry.I love feeding the homeless,and__20__in someone's life. | |||
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