已知,若存在,满足,则称是的     一个“友好”三角形. (i) 在满

 已知,若存在,满足,则称 

   一个“友好”三角形.

(i) 在满足下述条件的三角形中,存在“友好”三角形的是____:(请写出符合要求的条件的序号)

 ;②

      .

(ii) 若等腰存在“友好”三角形,且其顶角的度数为___.

答案

②;【考点】解斜三角形

【试题解析】

(i)对①:因为所以①不存在“友好”三角形;
对②:若
同理:故②存在“友好”三角形;
对③:若满足,则

都不能构成三角形,故③不存在“友好”三角形。
 (ii)
若等腰存在“友好”三角形,则A=B,所以A+A+C=
,分析知
所以
C=.即顶角的度数为

相关题目

“德意志民族曾经号称‘思想家和诗人的民族’,也涌现出
“德意志民族曾经号称‘思想家和诗人的民族’,也涌现出了一流的科学家和艺术家。……但是,这个伟大的民族有曾在一个狂人的操纵下进行过最骇
Jane told the police man that her gold necklace ______.    A. was stolen of 
Jane told the police man that her gold necklace ______.    A. was stolen of   B. was robbed from    C. had been stolen from   D. had been robbed of
某离子晶体的晶胞结构如图3-24所示。则该离子的化学式为
某离子晶体的晶胞结构如图3-24所示。则该离子的化学式为( ) 图3-24A.AB12C8              B.ABC3                C.AB2C3        
如图甲所示,用20N的水平拉力拉着质量为5kg的铝块在水平地
如图甲所示,用20N的水平拉力拉着质量为5kg的铝块在水平地面上运动,铝块运动的s﹣t图象如图乙所示,则铝块受到的摩擦力大小为N;若克服摩擦力所
SPECIAL EVENTS THIS WEEKEND Captain Goodfellow Do your children enjoy interestin
SPECIAL EVENTS THIS WEEKEND Captain Goodfellow Do your children enjoy interesting stories, funny games, and exciting dances? Captain Goodfellow will be ready to teach all these things to children of a
请先阅读几所大学所提供的健康医疗教育项目: A.Argosy Univer
请先阅读几所大学所提供的健康医疗教育项目: A.Argosy University Our postgraduate degree level education provides the knowledge and tools to create successful and meaningful career
The world of taxi drivers is dominated by men. But there is one small cab compa
The world of taxi drivers is dominated by men. But there is one small cab company in Delhi, where all the drivers and passengers are female. Women's safety is a hot topic in India at the moment, so
“距今约七十至二十万年,还保留了猿的某些特征,但手脚
“距今约七十至二十万年,还保留了猿的某些特征,但手脚分工明显,能够制造和使用工具”根据这一材料,请你判断他属于(   )A、元谋人     

最新题目