已知弦长L=2.93米，拱高H=0.305米，求圆心角A和弧长C？弧半径为R。R^2=(R-H)^2+(L/2)^2R^2=R^2-2*R*H+H^2+L^2/42*R*H=H^2+L^2/4R=H/2+L^2/(8*H)=0.305/2+2.93^2/(8*0.305)=3.5184米A=2*ARC SIN((L/2)/R)=2*ARC SIN((...
