Rational Functions Math Example 4
Follow the full solution, then compare it with the other examples linked below.
Example 4
hardFind all asymptotes (vertical, horizontal, and oblique) of . Does the function have a hole or a vertical asymptote at ?
Solution
- 1 Factor the numerator: . So .
- 2 The cancels: for . Since the factor cancels, is a hole (not a vertical asymptote). Hole at .
- 3 No vertical asymptotes remain. The simplified form is linear, so there is an oblique asymptote (which the function equals everywhere except the hole). No horizontal asymptote.
Answer
When a factor cancels between numerator and denominator, it creates a hole (removable discontinuity), not a vertical asymptote. The degree of the numerator exceeding the denominator by 1 indicates an oblique asymptote found by polynomial division.
About Rational Functions
A rational function is a ratio of two polynomials: where and are polynomials and .
Learn more about Rational Functions →