(x,1)=(x+a)+(x-a)]+|(5)d5 2 Lo(x +at)+o(x-at )I y(5)d2(t≤x/a) ux. t [p(x+ar)-(x-at)]+ v(s)ds (t2x/a) 2 v(5d5 2 2 d a u x t x at x at x at x at ( ) 2 1 [ ( ) ( )] 2 1 ( , ) =  + + − +   + −        + − − +  + + − +    + − + − ( ) ( / ) 2 1 [ ( ) ( )] 2 1 ( ) ( / ) 2 1 [ ( ) ( )] 2 1 ( , ) d t x a a x at x at d t x a a x at x at u x t x a t a t x x a t x a t           ( ) ( ) 2 1 ( ) 2 1 ( ) ( ) 2 1 ( ) 2 1 ( ) 2 1 ( ) 2 1 ( ) 2 1 ( ) 2 1 ( ) 2 1 ( / ) 0 0 0 0 ( ) 0 0 0 0                         d a d a d a d a d a d a d a d a d a t x a a t x x a t x a t x a t x a t x a t x a t x a t x a t x a t          − + − − + − + − + + − = + − − = +   =  +  = + − −