Some embedding inequalities in Hardy-Sobolev space are proved. Furthermore, by the improved inequalities and the linking theorem, in a new k-order SobolevHardy space, we obtain the existence of sign-changing solutions for the nonlinear elliptic equation {-△（k）u：=-△u-（N-2）2/4u/｜x｜2-1/4k-1∑im1u/｜x｜2（ln（i）R/｜x｜2=f（x,u）,x∈Ω,u=0,x∈Ω,where 0∈ΩBa（0）RN,n≥3,ln）i）=6jm1ln（j）,and R=ae（k-1）,where e（0）=1,e（j）=ee（j=1）for j≥1,ln（1）=ln,ln（j）=lnln（j-1）for j≥2.Besides,positive and negative solutions are obtained by a variant mountain pass theorem.
The Hardy-Sobolev inequality with general weights is established, and it is shown that the constant is optimal. The two weights in this inequality are determined by a Bernoulli equation. In addition, the authors obtain the Hardy-Sobolev inequality with general weights and remainder terms. By choosing special weights, it turns to be many versions of the Hardy-Sobolev inequality and the Caffarelli-Kohn-Nirenberg inequality with remainder terms in the literature.
