Solution:
Given the conditions;
[tex]As\text{ }x\rightarrow-\infty,y\rightarrow\infty\text{ and }x\rightarrow\infty,y\rightarrow\infty[/tex]
When;
[tex]x\rightarrow-\infty,y\rightarrow\infty[/tex]
Then, the degree of the polynomial is even.
Then, given three x-intercepts, it means one of the root could have been repeated.
Thus, the model function is;
[tex]f\lparen x)=\left(x+1\right)\left(x-3\right)\left(x^2\right)[/tex]
