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I’m not to sure how I would create a polynomial function from the graph any help or examples meeting the criteria?

I’m not to sure how I would create a polynomial function from the graph any help or-example-1
User Luke Vo
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1 Answer

18 votes
18 votes

Answer:

f(x) = 1/8(x +4)^2(x +1)(x -3)

Explanation:

The end behavior shows both ends of the graph headed to +∞. That means ...

  • the function is of even degree
  • the leading coefficient is positive

There are zeros at x=-4, -1, 3. The graph does not cross the x-axis at x=-4, so that zero has even degree. The smallest degree that will satisfy the degree requirements is 4, where the zero at x=-4 is of multiplicity 2.

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You know that zero x=p means (x-p) is a factor. The multiplicity is the exponent of the factor, so the factored function so far is ...

f(x) = (1/a)(x +4)^2(x +1)(x -3)

When x=0, this is ...

f(0) = 1/a(4^2)(1)(-3) = -48/a

The graph shows you the y-intercept is -6, so ...

-6 = -48/a

a = 8

The factored polynomial is ...


f(x)=(1)/(8)(x+4)^2(x+1)(x-3)

User Jan Tajovsky
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