在三角形ABC中,三边a,b,c成等差数列,sinA,sinB,sinC成等比数列,试判断三角形AB

在三角形ABC中,三边a,b,c成等差数列,sinA,sinB,sinC成等比数列,试判断三角形AB

a/sinA =b/sinB =c/sinC,且sinA,sinB,sinC成等比数列,所以b^2=ac.又a+c=2b.上面右边平方减去左边4倍.得（a-c)^2=0so:a=b=c.等边三角形.======以下答案可供参考======供参考答案1:2b=a+c,b^2=a*c,联立求解。发现（a-c）^2=0 所以a=c , 又因为2b=a+c=2a，所以是等边吧供参考答案2:a,b,c成等差数列，则sinA,sinB,sinC也成等差数列sinA,sinB,sinC也成等比数列，那么只能是sinA=sinB=sinC也就是a=b=c所以ABC是等边三角形供参考答案3:Happy whole family (front row center for the beam-Star) 15 years ago, they picked up a helpless disabled elderly Dangdie, neighbors are all thumbs. Ji recent years, it was found that they picked up the father suddenly become \Suddenly, praised gradually become supercilious. The face of all this,uggs australia, how should they do? \. \ \ \ \ whatever reason, had prompted his father to drive Xiao-Ping? This had to from 15 years ago. \Suddenly, the door knock on the door sounded. son, Wang Jun opened the door, the two strangers standing in front of the drenched, precisely, is a person carrying another person with a back pocket, back pockets of people still do not live groan. \ Jia-Qiang Wang looked for a long time, only to find the back pocket of the man is 3 months rent to live in their own homes before the tenant beam star, half months ago, only to leave from here. original, Liang star broke his leg, no money, was not any place to go, before returning here. \ Boy in the husband's opposition and his son, Jia-Qiang Wang's wife had spent the whole night Xiao-Ping Liang star sent to a nearby hospital. beam star is Kuanba retired workers, small big tongue, often drooling and also received injuries, the right hand mobility. He was married once, but a man without children, without parents after a divorce in 1995, without relying on, then rented a small hut of the Jia-Qiang Wang, less than 3 months will go ... ... pelvis dislocation beam star, spent a week in hospital before discharge. Meanwhile, Xiao-ping had boiled bone soup every day he sent for him, can not be paid that portion of medical expenses reimbursed. had Xiao-ping was not working, the family 300 yuan per mon

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