Citation:
A zero limit occurs when a function approaches zero as x approaches a certain value. This means that as x gets closer to that value, f(x) gets arbitrarily close to zero.
An asymptote is a line that a curve approaches but never touches or crosses. It can be horizontal, vertical, or slanted.
A discontinuity occurs when there is an abrupt break or jump in the graph of a function.
A rational function is any expression made up of polynomial functions divided by each other. It can have vertical asymptotes and holes in its graph.