已知弦长L=2.4米,弧高H=0.25米,求半径R? R^2=(R-H)^2+(L/2)^2 R^2=R^2-2*R*H+H^2+L^2/4 2*R*H=H^2+L^2/4 R=H/2+L:^2/(8*H) =0.25/2+2.4:^2/(8*0.25) =3.005米