可设P(5cost,4sint),其中0<=t<2pi
距离d=|4*5cost+3*4sint+36|/(4^2+3^2)^(1/2)
=(4/5)|5cost+3sint+9|
=(4/5)|(根号34)sin(t+k)+9|, 其中cosk=(3/34)(根号34), sink=(5/34)(根号34), k=arccos[(3/34)(根号34)]
=(4/...
可设P(5cost,4sint),其中0<=t<2pi
距离d=|4*5cost+3*4sint+36|/(4^2+3^2)^(1/2)
=(4/5)|5cost+3sint+9|
=(4/5)|(根号34)sin(t+k)+9|, 其中cosk=(3/34)(根号34), sink=(5/34)(根号34), k=arccos[(3/34)(根号34)]
=(4/...