Question

Discuss the relation advantages of formal and informal requirement specification

Answer 1

The formal methods model is concerned with the application of a mathematical technique to design and implement the software. This model lays the foundation for developing a complex system and supporting the program development. The formal methods used during the development process provide a mechanism for eliminating problems, which are difficult to overcome using other software process models. The software engineer creates formal specifications for this model. These methods minimize specification errors and this result in fewer errors when the user begins using the system.enerally, the formal method comprises two approaches, namely, property based and model-based. The property-based specification describes the operationsperformed on the system. In addition, it describes the relationship that exists amongthese operations. A property-based specification consists of two parts: signatures, which determine the syntax of operations and an equation, which defines the semantics of the operations through a set of equations known as axioms. 
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Answer 2

In a business there is need of a lot of things, to smoothly run the business, among those needs, some requirements are formal and some are informal. In the list of  formal requirements, there are several things like all the official stuffs including the paper works, payment processes, and managerial requirements.

In a business there are several informal requirements, like holding a party or hosting any cultural activity, and many other recreational activity for the employees.