‎using variational arguments‎, ‎we prove the existence of infinitely‎ ‎many solutions to a class of $p$-biharmonic equation in‎ ‎$mathbb{r}^n$‎. ‎the existence of‎ ‎nontrivial‎ ‎solution is established under a new‎ ‎set of hypotheses on the potential $v(x)$ and the weight functions‎ ‎$h_1(x)‎, ‎h_2(x)$‎.

and Applied Analysis 3 2.5. Laguerre Surface. LetΦ be a Laguerre surface inR. Any regular pointP onΦ is thus represented as in (16). Denote the corresponding isotropic surface by Φ with P given by (16). By duality, their corresponding curvatures are related by H ∗ = H K , K ∗ = 1 K . (17) Blaschke [6] defined the middle tangent sphere to be the tangent to the tangent plane P with radius