比较xkw的系数， 2(k+s+1(k+)c1+(k+s+1)c+1-2(k+s)c:+c4=0 2k+2s-1 (k+s+1(2k+2s+1) 2k 9=2 * Ck+1 G=0,C2=C3=.=0 yi(x)=cox2 =2(2k-1) 0:c4-T2k+2(2k+ ci- 2(-1 2.1 21。_22(-1)1 C1= 0 4.3 4 15 15 比较x k +s的系数， ( )( ) ( ) ( ) 1 1 2 1 1 2 0 k k k k k s k s c k s c k s c c + + + + + + − + + = + + ( )( ) 1 2 2 1 1 2 2 1 k k k s c c k s k s + + − = − + + + + 1 1 : 2 s = ( ) 1 2 , 3 2 2 2 k k k c c k k + =     + +   1 2 3 c c c = = =  = 0, 0 ( ) 1 2 1 0 y x c x = 2 s = 0 : ( ) ( )( ) ' ' 1 2 2 1 2 2 2 1 k k k c c k k + − = + + ( ) ' ' ' ' 1 0 0 0 2 1 2 , 2 1 2! c c c c − = = − = −  ( ) 2 ' ' ' ' 2 1 0 0 2 1 1 2 1 1 , 4 3 4! 6 c c c c  −  = = = − 