当ε〉0充分小时,Yang给出了R^4中的如下非线性方程Δ2u-div(a(x) u)+b(x)u=f(x,u)/|x|^β+εh(x) 有至少2个非平凡弱解的充分条件.在这个注记中,作者对非线性项给出了一个不同于Yang文章中(H5)的限制条件.在其他条件不变的情况下,同样得到了此方程的多解性.并且作者给出了一个例子,说明2篇文章中的限制条件是不能互相覆盖的.
For the nonlinear equationΔ2u-div(a(x) u)+b(x)u=f(x,u)/|x|^β+εh(x) when ε〉0 is small enough, Yang established sufficient conditions under which the equation has at least two non-trivial weak solutions. In this remark, the authors give an assumption which is different from the assumption (H5) in Yang. With other assumptions unchanged, the same multiplicity result is proved. The authors also give an example to show that the two assumptions can not cover each other.