【摘要】 利用算子理论及矩阵运算方法,讨论了由两类不同的对称微分算式D^（4）+D^（2）+q₁（t）和D^（4）+q₂（t）（D=d/dt,t∈I=[a,b]）生成的微分算子的积算子的自伴性,获得了积算子是自伴算子的充分必要条件.更多还原

【Abstract】 The self-adjointness of product operator L₁L₂ is investigated which operators L_i（i = 1,2） are generated by two different differential expressions D⁽（4） + D^（2） +q_l（t） and D^（4）+ q₂（t）（D=d/（dt）,t ε I =[a,b]） respectively.The sufficient and necessary conditions of product operator L₁L₂ which is self-adjoint are obtained with operators theory and matrix calculation method.更多还原