Recursive Equations: Formal Methods- the question is as follows

This question is written in VDM-Sl language

Consider the recursive equation f: int int-> int f (x,y) == if x = 0 then 1 else y. f(x - 1,y) (a) Use the definition of f to evaluate f(0,2), f(1,2),f (2,2). (b) Suggest a fixed point solution for the functional T1(F,x,y) == if x = 0 then 1 else y* F(x 1,y) (c) Verify that your suggestion is in fact a fixed point solution for T1. (d) Is the function f always defined? Explain your answer. (e) Suggest a least fixed point solution for T1. Consider the recursive equation f: int int-> int f (x,y) == if x = 0 then 1 else y. f(x - 1,y) (a) Use the definition of f to evaluate f(0,2), f(1,2),f (2,2). (b) Suggest a fixed point solution for the functional T1(F,x,y) == if x = 0 then 1 else y* F(x 1,y) (c) Verify that your suggestion is in fact a fixed point solution for T1. (d) Is the function f always defined? Explain your answer. (e) Suggest a least fixed point solution for T1