Draw the graph and find the points of discontinuity for `f(x)=[x^(2)-x-1],x in[-1,2]` ([.] represents the greatest integer function).

Explanation

`f(x)=[x^(2)-x-1], x in [-1,2]`
Let us first draw the graph of `y=x^(2) -x-1,` which is upward parabola having vertex at `(1//2, -5//4)`

The graph of `f(x)=[x^(2)-x-1]` can be drawn as shown in the following figure.