1、章三角函数8函数yAsin(x)图像与性质(一)学习目标1.理解yAsin(x)中、A对图像的影响.2.掌握ysin x与yAsin(x)图像间的变换关系,并能正确地指出其变换步骤.题型探究问题导学内容索引当堂训练问题导学思考1知识点一(0)对函数ysin(x),xR的图像的影响如何由yf(x)的图像变换得到yf(xa)的图像?答案答案答案向左(a0)或向右(a0)平移|a|个单位.思考2如何由ysin x的图像变换得到ysin(x )的图像?答案答案答案向左平移 个单位.梳理梳理如图所示,对于函数ysin(x)(0)的图像,可以看作是把ysin x的图像上所有的点向 (当0时)或向 (当1时
2、)或 (当01时)或 (当0A0)个单位长度后,所得图像对应的函数为偶函数,则m的最小值为答案解析当堂训练2341答案51.函数ycos x图像上各点的纵坐标不变,把横坐标变为原来的2倍,得到图像的解析式为ycos x,则的值为答案23415答案23415解析4.将函数ysin(2x)的图像向左平移 个单位长度,所得函数图像的解析式为 .23415答案解析ycos 2x答案解析23415规律与方法1.由ysin x的图像,通过变换可得到函数yAsin(x)(A0,0)的图像,其变化途径有两条:注意:两种途径的变换顺序不同,其中变换的量也有所不同:(1)是先相位变换后周期变换,平移|个单位(2)
3、是先周期变换后相位变换,平移 个单位,这是很易出错的地方,应特别注意2.类似地,yAcos(x)(A0,0)的图像也可由ycos x的图像变换得到本课结束团Tiffany,a 16yearold girl,was very shy.Last September,her best frien“I was really sad the moment I heard the bad news and I didnt know what to do,”Tiffany recalled.“I shut myself in my room for a whole week.It was then that
4、 my aunt took me to a sports club one Saturday and I saw so many young people playing different kinds of sports there.I signed up for a beginners course in volleyball and since then I have been playing this sport.Now I practice twice a week there.It is wonderful playing sports in this club and I hav
5、e made lots of friends as well.2 ”The most basic aim of playing sports is that you can improve your health even if you are not very good at sports.Besides,you can get to know a circle of people at your age while playing sports.3 Since she joined the sports club,s I got used to the life here.And now
6、I know lots of(5)_ here.For example,when I meet my friend on the street,I usually(6)_ him like this,“Hey,where are you going?”In our country if someone asks this,people may get(7)_ but in this country people wont.Of course,there are some other interesting things here.Ill tell you about them next tim
7、e.he has opened up herself and now she has become very active and enjoys meeting and talking with others.1Its polite for girls to kiss each other on the side of the face.s also become more confident.团圆圆一家在台湾可受欢迎了。每天,小朋友们排着长队,等着跟它们合影留念。从“排着长队”体现出每天喜欢它们的人不计其数,特别受选D.A.根据同类项合并法则,与不是同类项,不能合并,故本选项错误;B.根据算术平方根的定义,=3,故本选项错误;C.根据同底数幂的乘法aa2=a3,故本选项错误;D.根据积的乘方,(2a3)2=4a6,故本选项正确.欢迎。从“合影留念”体现出大家都想和大熊猫留住最美丽的瞬间以作纪念。Nothing can be accomplished without norms or standards.精品资料!感谢阅读下载!