设函数 f (x)=acos2x+(a-1)(cosx+1)，其中 a>0，记| f (x)| 的最大值为 A，
(Ⅰ)求 f '(x);
(Ⅱ)求 A;
(Ⅲ)证明 |f '(x)|≤2A
正确答案：
答案解析：
暂无解析
设函数 f (x)=acos2x+(a-1)(cosx+1)，其中 a>0，记| f (x)| 的最大值为 A，
(Ⅰ)求 f '(x);
(Ⅱ)求 A;
(Ⅲ)证明 |f '(x)|≤2A
暂无解析
马克思说：“在美国历史上，林肯必将与华盛顿齐名。”其理由是他们都
在实验中进行下列实验，括号内的实验用品都能用到的是（）
“Earlytobed，earlytorise”makesamanhealthy,wealthyandwise.It'sgoodforthebody.Thisisanoldsaying.Haveyouheardofitbefore?Itmeansthatwemustgotobedearlyatnight，andgetupearlyinthemorning.Thenweshallbehealthy.Weshallalsoberichandclever.Thatistrue.Thebodymusthaveenoughsleeptobehealthy.Childrenofyoungageshouldhaveenoughsleep，ortheycan'tdotheirworkverywell.Theywillnotbewiseandtheymaynotbecome。wealthy!.Thebodyalsoneedsexercise:walking,running,jumping,swimming,playinggamesandallother。exercise.Exercisekeepsthebodystrong.Exercisealsohelpsthebloodtomovearoundinsidethe.body.Thisisveryimportant.Ourbloodtakesfoodtoallpartsofourbody.Theheadalsoneeds.blood.Exercisehelpsustothinkbetter.
根据短文内容，回答问题.
1.Whatdoes“earlytobed.earlytorise”mean?
2.Whatmustthebodyhavetobehealthy?
3.WhatwillhappentoChildrenofyoungagewhodon'thaveenoughsleep?
4.Whatkeepsthebodystrong?
5.Whattakesfoodtoallpartsofourbody?
将蛙离体神经纤维置于某种培养液中，给予适宜刺激并记录其膜内钠离子含量变化及膜电位变化，分别用图中曲线Ⅰ、Ⅱ表示。下列有关说法正确的是