证明三角形的面积:S=a2sinBsinc∕2sinA=b2sinAsinC/2sinB=c2sinAsinB/2sinc
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![证明三角形的面积:S=a2sinBsinc∕2sinA=b2sinAsinC/2sinB=c2sinAsinB/2sinc](/uploads/image/z/3755804-68-4.jpg?t=%E8%AF%81%E6%98%8E%E4%B8%89%E8%A7%92%E5%BD%A2%E7%9A%84%E9%9D%A2%E7%A7%AF%EF%BC%9AS%3Da2sinBsinc%E2%88%952sinA%3Db2sinAsinC%EF%BC%8F2sinB%3Dc2sinAsinB%EF%BC%8F2sinc)
证明三角形的面积:S=a2sinBsinc∕2sinA=b2sinAsinC/2sinB=c2sinAsinB/2sinc
证明三角形的面积:S=a2sinBsinc∕2sinA=b2sinAsinC/2sinB=c2sinAsinB/2sinc
证明三角形的面积:S=a2sinBsinc∕2sinA=b2sinAsinC/2sinB=c2sinAsinB/2sinc
由正弦定理,b=asinB/sinA,
∴△ABC的面积S=(1/2)absinC=a^2*sinBsinC/(2sinA),
同理,S=b^2*sinAsinC/(2sinB)=c^2*sinAsinB/(2sinC).