Using limits, the end behavior of the functions are given as follows:
a. Rises to the left and falls to the right.
b. Rises to the left and rises to the right.
c. Falls to the left and rises to the right.
How to find the end behavior of a function f(x)?
The end behavior of a function f(x) is given by the limit of f(x) as x goes to infinity.
In item a, we have that, respectively, to the left and to the right.
[tex]\lim_{x \rightarrow -\infty} f(x) = \lim_{x \rightarrow -\infty} -5x^3 = -5(-\infty)^3 = \infty[/tex]
[tex]\lim_{x \rightarrow \infty} f(x) = \lim_{x \rightarrow \infty} -5x^3 = -5(\infty)^3 = -\infty[/tex]
Hence it rises to the left and falls to the right.
In item b, we have that, respectively, to the left and to the right.
[tex]\lim_{x \rightarrow -\infty} f(x) = \lim_{x \rightarrow -\infty} 3x^6 = 3(-\infty)^6 = \infty[/tex]
[tex]\lim_{x \rightarrow \infty} f(x) = \lim_{x \rightarrow \infty} 3x^6 = 3(\infty)^6 = \infty[/tex]
Rises to the left and rises to the right.
In item c, we have that, respectively, to the left and to the right.
[tex]\lim_{x \rightarrow -\infty} f(x) = \lim_{x \rightarrow -\infty} 20x^3 = 20(-\infty)^3 = -\infty[/tex]
[tex]\lim_{x \rightarrow \infty} f(x) = \lim_{x \rightarrow \infty} 20x^3 = 20(\infty)^3 = \infty[/tex]
Falls to the left and rises to the right.
More can be learned about limits and end behavior at https://brainly.com/question/22026723
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