角度 弧度 角度 R= 30 α= 80 1.745329 R= 10 α= 50 l(玄长) = 45.963 l(玄长) = 18.126 h= 19.284 h= 4.226 h’= 27.388 h’= 19.436 h''= 16.672 h''= 13.662 S1扇= 785.398 S1扇= 113.446 S2= 443.163 S2= 38.302 S3= 629.415 S3= 176.148 代求面积 = 287.180 143.590035 代求面积 = 101.004 5.400 1550.772 775.3861888 1252.453 2803.23 角度 弧度 角度 R= 15 α= 98.2562 1.426698 R= 20 α= 128.4216 l(玄长) = 19.631 l(玄长) = 17.402 h= 11.343 h= 18.008 h’