elliptic equation的用法和樣例：
例句
- In chapter two, we prove the existence of nontrivial solutions for the elliptic equation of high order.
在第二章中，我們討論了一類(lèi)高階橢圓方程，并且證明了多解的存在性問(wèn)題。 - It is known that there are many methods to study the convexity for second order elliptic PDE.
摘要對于半線(xiàn)性二階橢圓方程，已有多種方法研究其解的凸性。
