cosC=(a^2+b^2-c^2)/(2ab)sinC=√(1-cos^2C)=√[4a^2b^2-(a^2+b^2-c^2)^2]/(2ab)absinC/2=ch/2h=absinC/c={ab√[4a^2b^2-(a^2+b^2-c^2)^2]/(2ab)}/c=√[4a^2b^2-(a^2+b^2-c^2)^2]/(2c)