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for each function below, find all horizontal and vertical asymptotes. you must support your conclusions by using limits. (a) f(x) = 12x 2 x − 6 2x 2 x − 1 . (b) h(x) = e x 3 3 − e 2x .

User Hardy
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Final answer:

The function f(x) has a horizontal asymptote at y = 6 and a vertical asymptote at x = 3. The function h(x) does not have traditional horizontal or vertical asymptotes as it is dominated by exponential growth and decay.

Step-by-step explanation:

To find the horizontal and vertical asymptotes of the provided functions, we must examine the behavior of the functions as x approaches infinity and the points where the functions are undefined due to denominator being zero.

f(x) = \( \frac{12x}{2x - 6} \)

For horizontal asymptotes, we look at the limits as x approaches infinity. Since the degrees of the numerator and denominator are the same, the horizontal asymptote can be found by dividing the leading coefficients. As x approaches infinity:

\( \lim_{x \to \infty} \frac{12x}{2x - 6} = \frac{12}{2} = 6 \)

Thus, the horizontal asymptote is y = 6.

For vertical asymptotes, they occur where the function is undefined:

2x - 6 = 0

x = 3

As x approaches 3, the denominator approaches 0, and the function approaches infinity. Therefore, the vertical asymptote is x = 3.

h(x) = \( e^{\frac{x}{3}} - e^{2x} \)

For the function h(x), it is not rational, so it does not have vertical asymptotes in the same way as rational functions. However, we can still investigate the limits. As x approaches infinity, \( e^{\frac{x}{3}} \) and \( e^{2x} \) both grow towards infinity, but \( e^{2x} \) grows much faster. Hence, the function h(x) will be dominated by \( -e^{2x} \), and:

\( \lim_{x \to \infty} (e^{\frac{x}{3}} - e^{2x}) = -\infty \)

Thus, h(x) will not possess a horizontal asymptote as it approaches negative infinity. As x approaches negative infinity, \( e^{\frac{x}{3}} \) approaches 0 faster than \( -e^{2x} \) approaches 0. The limit of h(x) as x approaches negative infinity is therefore 0, but since the function becomes negative before crossing zero, there's no horizontal asymptote.

User Ibotty
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