由cosA=4/5,可知A为锐角,进而sinA=3/5,由正弦定理a/sinA=b/sinB得
a/(3/5)=√3/sin(π/3),解得a=6/5
面积=(1/2)absinC=(1/2)*(6/5)*√3*sin(π-A-B)=(3√3/5)sin(A+B)
=(3√3/5)(sinAcosB+cosAsinB)
=(3√3/5)[(3/5)cos(π/3)+(4/5)sin(π/3)]
=(3√3+12)/10
由cosA=4/5,可知A为锐角,进而sinA=3/5,由正弦定理a/sinA=b/sinB得
a/(3/5)=√3/sin(π/3),解得a=6/5
面积=(1/2)absinC=(1/2)*(6/5)*√3*sin(π-A-B)=(3√3/5)sin(A+B)
=(3√3/5)(sinAcosB+cosAsinB)
=(3√3/5)[(3/5)cos(π/3)+(4/5)sin(π/3)]
=(3√3+12)/10