A quadratic function fx is shown select symbols and value to
     A quadratic function f(x) is shown  select symbols and value to restrict the domain of f(x) so that f^-1(x), is a function and the domain of f(x) includes x = -4   
  
  Solution
you can make 2 functions out of it
1st one can be:
 (-inf , +6]
2nd one can be
 [+6, +inf)
This is for the 1st part and last part of the quadratic equations respectively

