how to find horizontal asymptotes
how to find horizontal asymptotes
Answer:
To find the horizontal asymptotes of a function, you need to determine what happens to the function as x approaches positive or negative infinity. Here are the steps to follow:
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Take the limit of the function as x approaches positive or negative infinity.
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If the limit is a finite number (i.e., it approaches a specific value), then this is the horizontal asymptote.
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If the limit does not exist (i.e., it approaches infinity or negative infinity), then there is no horizontal asymptote.
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If the limit is zero, you will need to perform further analysis to determine if there is a horizontal asymptote.
Here’s an example: Let’s say we want to find the horizontal asymptote of the function f(x) = (2x^3 + 5x^2 - 8x) / (3x^3 + 9x^2 - 2x - 6).
- Take the limit of the function as x approaches positive infinity: lim(x->∞) (2x^3 + 5x^2 - 8x) / (3x^3 + 9x^2 - 2x - 6) = lim(x->∞) (2 + 5/x - 8/x^2) / (3 + 9/x - 2/x^2 - 6/x^3) = 2/3
- Take the limit of the function as x approaches negative infinity: lim(x->-∞) (2x^3 + 5x^2 - 8x) / (3x^3 + 9x^2 - 2x - 6) = lim(x->-∞) (2 - 5/x - 8/x^2) / (3 - 9/x - 2/x^2 - 6/x^3) = 2/3
Since both limits are equal to 2/3, the horizontal asymptote of the function is y = 2/3