a,b,c成等比数列
b^2=ac
a^2,b^2,c^2成等差数列
2b^2=a^2+c^2=2ac
(a-c)^2=0
a=c=b
所以是等边
∠B=60°
已知在△ABC中三边a,b,c成等比数列,且a^2,b^2,c^2成等差数列,求角B
已知在△ABC中三边a,b,c成等比数列,且a^2,b^2,c^2成等差数列,求角B
数学人气:542 ℃时间:2020-02-05 13:52:39
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