biquadratic form

例句：

1. 1.In the study of linear programming, the biquadratic form is a key concept.
   在线性规划研究中，双二次形式是一个关键概念。
2. 2.The biquadratic form is used to solve quadratic equations with two variables.
   双二次形式用于解决有两个变量的二次方程。
3. 3.The biquadratic form can be used to model complex systems that exhibit nonlinear behavior.
   双二次形式可以用来建模表现出非线性行为的复杂系统。