1. 4.3 Rational Functions I

2. A rational function is a function of the form
Where p and q are polynomial functions and q is not the zero polynomial. The domain consists of all real numbers except those for which the denominator is 0.

3. Find the domain of the following rational functions:
All real numbers except -6 and-2.
All real numbers except -4 and 4.
All real numbers.

5. y
Horizontal Asymptotes
y = R(x)
y = L x y
y = L x
y = R(x)

6. Vertical Asymptotes
x = c y x
x = c y x

7. If an asymptote is neither horizontal nor vertical it is called oblique.x

8. Theorem Locating Vertical Asymptotes
A rational function
In lowest terms, will have a vertical asymptote x = r, if x - r is a factor of the denominator q.

9. Vertical asymptotes: x = -1 and x = 1
Find the vertical asymptotes, if any, of the graph of each rational function.
Vertical asymptotes: x = -1 and x = 1
No vertical asymptotes
Vertical asymptote: x = -4

10. Consider the rational function
1. If n < m, then y = 0 is a horizontal asymptote of the graph of R.
2. If n = m, then y = an / bm is a horizontal asymptote of the graph of R.
3. If n = m + 1, then y = ax + b is an oblique asymptote of the graph of R. Found using long division.
4. If n > m + 1, the graph of R has neither a horizontal nor oblique asymptote. End behavior found using long division.

11. Find the horizontal and oblique asymptotes if any, of the graph of
Horizontal asymptote: y = 0
Horizontal asymptote: y = 2/3

12. Oblique asymptote: y = x + 6