Limits of Functions

You can take the limit of a function as the variable approaches 
a fixed number for a defined function f:
> f := x -> (x^2 -4)/(x-2);

                                      2
                                     x  - 4
                           f := x -> ------
                                     x - 2

> limit(f(x), x=2);

                                  4

Graph the function to check if this limit seems correct:
> plot(f, -5..5);

> factor(f(x));

                                x + 2

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