0=x(a-x) h=x(a-x) w(x,0)=2(4,+B, )sin nx=x(a-x) w(x,b)=2(A, exp[1+B, exp[-1)sin"-=x(a-x) 4的联立代数方程 xa-x)=∑cnsi nIX A,+B n兀b A, exp[-]+ B exp/-nr60 ( ) w x a x y= = − ( ) w x a x y b= = − 1 ( ,0) { }sin ( ) n n n n x w x A B x a x a   = = + = −  1 ( , ) { exp[ ] exp[ ]}sin ( ) n n n n b n b n x w x b A B x a x a a a     = = + − = −  , A B n n 的联立代数方程 1 ( ) sin n n n x x a x C a   = − =  A B C n n n + = exp[ ] exp[ ] n n n n b n b A B C a a   + − =