弧长度C=13米,高度H=3米,求弦长L?弧半径为R,弧所对的圆心角为A.Rn+1=(1-(Rn*COS(C/(2*Rn))-Rn+H)/((C/2)*SIN(C/(2*Rn))-H))*RnR0=7R1=6.3878R2=6.4671R3=6.4688R4=6.4688R=6.4688A=C/R=13/6.4688=2.009646弧度=2.009...