This file demonstrates the concept of limit of a function, as well as left and right limits of a function (which can be turned on and off). Set your function in the input box at the lower right. Then choose a value (slider i) at which you'd like to explore the limit. The slider g tells how far above/below the x-value in question the function is being evaluated. For example, if you're considering then set i = 2. If g = 3 then the function is being evaluated at 2 - 3 = -1 and 2 + 3 = 5. As g decreases, you'll be evaluating the function at values closer to i.