求三角形的面积在ABC中,A=450,B=600,AB=2,求ABC的面积．(精确到0.01)

Question

求三角形的面积
在 ABC中,A=450,B=600,AB=2,求 ABC的面积．(精确到0.01)

Answer 1

设AB边上的高是CD,其中D为垂足,且CD = h,则AD = h/tanA = hBD = h/tanB = h/√3而且AB = AD+BD = (1+1/√3)h = 2于是h = 2/(1+1/√3)△ABC的面积为1/2·AB·h = 2/(1+1/√3) = 2√3/（√3 + 1）= √3（√3 -1）= 3 -...