求翻译：本文主要研究二阶椭圆问题的混合有限元方法。首先，我们基于余能原理的变分形式，设中间变量，并引入空间及其范数，导出此二阶椭圆问题的混合模型。然后，应用最低阶的混合元，我们构造网格上单元和边的基函数，接着采用方法，将此模型问题转化为一个线性代数方程组，从而转化为求解方程组的系数。最后，通过我们可以得到近似解与真解的误差估计以及收敛阶，从而验证了应用最低阶元的混合有限元方法的正确性与准确性。是什么意思？

This paper studies the second-order elliptic problems, mixed finite element method. First, based on the variational form of the energy principle, we set up the intermediate variables, and the introduction of space and its norm, and export the hybrid model of second order elliptic problem. Then, the

This article examines an ellipse 2 bands of mixed finite element methods. First of all, we can be more than theory based on the forms, set the variable, and the introduction of space and the van, the export of a 2nd-order elliptic problems of the hybrid model. And then, the application of the minimu

This major study of mixed finite element method for second order elliptic problem. First of all, we are based on the variational form of complementary energy principle, set%2