我们知道,如果一个四边形可以将其压缩变形,那么变形到某一程度,会得到一个面积最大的四边形.现在要研究的就是该四边形压缩变形到什么情况下,可以使所得新四边形的面积最大?最大面积与各边长有什么关系? We know that if a quadrilateral can compress and deform it, then to a certain degree of deformation, a quadrangle with the largest area will be obtained. Now what we need to study is the quadrilateral compression deformation. Under what circumstances can the area of ​​the resulting new quadrilateral be maximized? What is the relationship between the maximum area and the length of each side?