A1.FIF.1*
      Extend previous knowledge of a function to apply to general behavior and features of a function.
(a)
Understand that a function from one set (called the domain) to another set (called the range assigns to each element of the domain exactly one element of the range.
(b)
Represent a function using function notation and explain that f(x) denotes the output of function f that corresond to the input x .
(c)
Understand that the graph of a function labeled as f is the set of all ordered pairs (x,y) that satisfy the equation y = f(x)