已知弧长C=285,弦到弧的高H=15,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))*Rn
R0=600
R1=659.67
R2=673.74
R3=674.36
R4=674.36
R=674.36
A=C/R
=285/674.36
=0.42262弧度
=0.42262*180/PI
=24.21度
L=2*R*SIN(A/2)
=2*674.36*SIN(24.21/2)
=282.88