o偶然间o
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因为a²+c²-b²=ac
又cosB=( a²+c²-b²)/(2ac)=1/2
故:B=π/3
因为(log 4 SinA)+(log 4 sinC)=log [4](sinAsinC)=-1
故:sinAsinC=1/4
因为A+B+C=π
故:C=2π/3-A
故:sinAsin(2π/3-A)=1/4
故:sin(2A+π/3)=1
故:2A+π/3=π
故:A=π/3
故:C=π/3
故:a=b=c
又:△ABC面积S=√3=1/2acsinB
故:a=b=c=2
1年前
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