R, (=cr+d, rt+) y(r)=P(r) ∴P<上:L (,0)=∑crP(x)( 米 =0 (这一结果后面例子要用) 又如图所示:d arcose+r 1 ∵X=cosO ∑crP(x)B) 2rx t l=0( ) l - 1 (l ) Rl l l r c r d r + = + ( ) ( ) l y x = P x ( ) ( ) ( ) 0 1: , l l l l r u r q c r P x ¥ = \ < = å * * (这一结果后面例子要用) 又如图所示: 2 1 1 1- 2 cos u d r r q = = + ( ) ( ) ( ) 2 0 1 cos 1- 2 l l l l x c r P x B rx r q ¥ = = \ = å + Q