题目
题型:不详难度:来源:
![](http://img.shitiku.com.cn/uploads/allimg/20191020/20191020031527-99695.png)
![](http://img.shitiku.com.cn/uploads/allimg/20191020/20191020031527-50249.png)
![](http://img.shitiku.com.cn/uploads/allimg/20191020/20191020031527-99695.png)
![](http://img.shitiku.com.cn/uploads/allimg/20191020/20191020031527-99695.png)
(1)求函数f(A)的最大值;
(2)若f(A)=0,C=
![](http://img.shitiku.com.cn/uploads/allimg/20191020/20191020031528-62931.png)
![](http://img.shitiku.com.cn/uploads/allimg/20191020/20191020031528-37404.png)
答案
![](http://img.shitiku.com.cn/uploads/allimg/20191020/20191020031528-13108.png)
解析
![](http://img.shitiku.com.cn/uploads/allimg/20191020/20191020031527-99695.png)
![](http://img.shitiku.com.cn/uploads/allimg/20191020/20191020031527-99695.png)
![](http://img.shitiku.com.cn/uploads/allimg/20191020/20191020031527-99695.png)
![](http://img.shitiku.com.cn/uploads/allimg/20191020/20191020031527-99695.png)
![](http://img.shitiku.com.cn/uploads/allimg/20191020/20191020031528-13108.png)
![](http://img.shitiku.com.cn/uploads/allimg/20191020/20191020031528-83059.png)
因为0<A<π,所以-
![](http://img.shitiku.com.cn/uploads/allimg/20191020/20191020031529-13082.png)
![](http://img.shitiku.com.cn/uploads/allimg/20191020/20191020031529-13082.png)
![](http://img.shitiku.com.cn/uploads/allimg/20191020/20191020031529-50502.png)
当A-
![](http://img.shitiku.com.cn/uploads/allimg/20191020/20191020031529-13082.png)
![](http://img.shitiku.com.cn/uploads/allimg/20191020/20191020031529-77593.png)
![](http://img.shitiku.com.cn/uploads/allimg/20191020/20191020031529-50502.png)
![](http://img.shitiku.com.cn/uploads/allimg/20191020/20191020031528-13108.png)
(2)由题意知f(A)=
![](http://img.shitiku.com.cn/uploads/allimg/20191020/20191020031528-13108.png)
![](http://img.shitiku.com.cn/uploads/allimg/20191020/20191020031528-83059.png)
![](http://img.shitiku.com.cn/uploads/allimg/20191020/20191020031528-83059.png)
又知-
![](http://img.shitiku.com.cn/uploads/allimg/20191020/20191020031529-13082.png)
![](http://img.shitiku.com.cn/uploads/allimg/20191020/20191020031529-13082.png)
![](http://img.shitiku.com.cn/uploads/allimg/20191020/20191020031529-50502.png)
![](http://img.shitiku.com.cn/uploads/allimg/20191020/20191020031529-13082.png)
![](http://img.shitiku.com.cn/uploads/allimg/20191020/20191020031529-13082.png)
因为C=
![](http://img.shitiku.com.cn/uploads/allimg/20191020/20191020031528-62931.png)
![](http://img.shitiku.com.cn/uploads/allimg/20191020/20191020031529-59590.png)
![](http://img.shitiku.com.cn/uploads/allimg/20191020/20191020031530-95670.png)
由
![](http://img.shitiku.com.cn/uploads/allimg/20191020/20191020031530-31349.png)
![](http://img.shitiku.com.cn/uploads/allimg/20191020/20191020031530-48266.png)
核心考点
试题【在△ABC中,内角A,B,C所对的边分别为a,b,c,且f(A)=2cos sin+sin2-cos2.(1)求函数f(A)的最大值;(2)若f(A)=0,C=】;主要考察你对解三角形应用等知识点的理解。[详细]
举一反三
![](http://img.shitiku.com.cn/uploads/allimg/20191020/20191020031519-93126.png)
(1)求cos(A+C)的值;
(2)求sin
![](http://img.shitiku.com.cn/uploads/allimg/20191020/20191020031519-96735.png)
(3)若
![](http://img.shitiku.com.cn/uploads/allimg/20191020/20191020031520-46948.png)
![](http://img.shitiku.com.cn/uploads/allimg/20191020/20191020031520-16048.png)
A.30°或60° | B.45°或60° |
C.120°或60° | D.30°或150° |
A.![]() | B.1 | C.![]() | D.2 |
![](http://img.shitiku.com.cn/uploads/allimg/20191020/20191020031506-40436.png)
![](http://img.shitiku.com.cn/uploads/allimg/20191020/20191020031506-42597.png)
A.![]() | B.![]() | C.![]() | D.![]() |
最新试题
- 1______ the shoes under the bed? [ ]A. Who"s B. Who"re C.
- 2下面有关热学内容的若干叙述正确的是( )A.气体密封在坚固容器中且温度升高,则分子对器壁单位面积的平均作用力增大B.物体
- 3质量不同的两个物体,放在同一粗糙水平面上,在相同力F作用下,都从静止开始运动,若两个物体与粗糙水平面间的摩擦系数相同,则
- 4— Happy Spring Festival! — _____________A.Yes, I’m happy.
- 5下列有关实验原理或实验操作正确的是A.用蒸馏水湿润的pH试纸测量某溶液的pH=10B.用10 mL量筒量取0.50 mo
- 6小题1: As we know, Thursday is the f__________ day in a week.小
- 7某同学发现家里储存的橘子长毛了,而且是青绿色的。他根据学过的知识,判断该“毛”属于( )A.霉菌B.大肠杆菌C.乳
- 8隋朝的统治类似于下列哪个朝代:[ ]A.秦朝B.东汉C.东晋D.唐朝
- 9-____do you usually eat breakfast?-At 7:30.A.WhatB.When time
- 10下列说法正确的是( )A.手持量筒量取一定体积的液体B.用托盘天平称量5.65g食盐C.铁、氮气、氯化钠分别是由分子、
热门考点
- 1The statue standing in the middle of the square has been bui
- 2给出平面区域如图所示,若使目标函数Z=ax+y(a>0),取得最大值的最优解有无数个,则a值为 ______
- 3下列各项中对 “者”的意义和用法不同的一项是【 】A.客之美我者,欲有求于我也。B.石之铿然有声者,所在皆是也。C.马之
- 4下列人类历史上的信息和信息传播活动的变革,按从古到今的时间顺序排列的有( )A.文字的诞生到语言的诞生B.文字的诞生到
- 5—Listen! There is a knock on the door.Who _____ it be?—It mu
- 6已知平行四边形ABCD中,∠A=58°,则∠B的度数是( )。
- 7法轮功邪教组织头目李洪志说,他通过发功能使铝发生化学反应,变成铜和金。请根据化学知识来判断正误,并提出你的理由。
- 8不等式x2≤1的解集是( )A.{x|x≤1}B.{x|x≤±1}C.{x|-1≤x≤1}D.{x|x≤-1}
- 9如图,是小亮在镜中看到身后墙上的时钟,此时的实际时刻是 。
- 10为了揭开原子内部结构的奥秘,1911年著名物理学家卢瑟福等人做了一个著名的“卢瑟福实验”:用一束带正电的质量比电子大很多