Finite element method can be applied to simplify any mathematical problem. The first answer is approximate with the accuracy depending on how well the finite elements are selected to resemble the exact math function. Note that finite elements do not have to be straight line segments or flat shaped elements. Any segment of a curved function can be applied as a finite element. So the accuracy can be quite good with few iterations.

The integral calculus and much of solid geometry was developed from and proved by use of finite elements.