Final answer:
Functional and nonfunctional requirements documents serve to create a detailed communication channel that outlines system specifications and ensures effective dialogue about system performance and needed improvements.
Step-by-step explanation:
Functional and nonfunctional requirements documents are used to facilitate communication between the users and a system, help exercise control over the inner workings of the firm, and ensure that the mathematical model of operation is well documented to demonstrate performance and effectiveness. These documents serve as a critical mechanism to communicate results and requirements, ensuring regular conversations about system functionality and improvements. Furthermore, they allow for the detailed documentation of organizational features to address cultural awareness and articulate how the system functions for different audiences.