在三角形ABC中,B=45度,C=60度,a=2(1+根号3),求三角形ABC的面积

2024-12-21 10:47:12
推荐回答(1个)
回答1:

A=180-45-60=75度
a/sinA=b/sinB
2(1+√3)/sin75=b/sin45
2(1+√3)/[(√6+√2)/4]=b/(√2/2)
2(1+√3)/[√2/2*(√3+1)/2]=b/(√2/2)
2(1+√3)/[(√3+1)/2]=b
b=2(1+√3)/[(√3+1)/2]
b=4(1+√3)/(√3+1)
b=4

S=1/2*absinC
=1/2*2(1+√3)*4*√3/2
=2(1+√3)*√3
=2√3+6