证明：存在实数X,使得SIN x+cos X=60°
题目
证明：存在实数X,使得SIN x+cos X=60°
答案
首先要熟悉三角函数变化：sinx+cosx=√2sin(x+45°),它的取值范围是[-√2,√2]
而60°=Pi/3
举一反三
我想写一篇关于奥巴马的演讲的文章,写哪一篇好呢?为什么好
最新试题
- Nina,who was eight ____ old,brought her report card home___school.She was very ____,because her
- 英语猜字谜:when do you go as fast as raching car?
- 总结各种时态的被动语态（不同形式）
- 如何用兆欧表测接地电阻
- 用1,2,3,4,5排成无重复数字的五位数,则这些数能被2整除的概率是
- 核电站利用_能发电，它的核心设备是核反应堆，核反应堆是通过可控_反应释放能量的．
- We can do something to help protect our environment at home.We can recycle things made of.
- 一个热水壶
- 求jeep,cat,bus,boy,hand,watch,sheep,woman,child,flower.的复数形式,每个都要.
- H2SO4+Fe=H2+?
热门考点