Limit of a function

Approach a point from the left and right, then watch the function values move toward a common value — or fail to do so.

x-min
x-max
f(x) left: x = a − h right: x = a + h x = a
Left-side value
Right-side value
Function value at a
Observation
Classroom idea: Pause the marker and ask students: "Do the left-hand and right-hand y-values approach the same number?" If yes, discuss the limit. If not, ask whether the problem is a jump, asymptote, or oscillation.