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help please 50 points Tia and Marcus are having a debate about the graph below. Tia says that this is an x^5 function while Marcus claims that it is an x^4 function. Find the fully factored form of this equation and determine who is correct in the debate. You can use the end behavior chart to help you explain your reasoning.

help please 50 points Tia and Marcus are having a debate about the graph below. Tia-example-1

1 Answer

10 votes

Answer:


f(x) = \frac14(x + 1)^2(x + 3)(x -2)( x - 3)

Tia is correct

Explanation:

From inspection of the graph, we can say that the leading coefficient of the function is positive as:


f(x) \rightarrow - \infty, \textsf { as } \ x \rightarrow - \infty\\f(x) \rightarrow +\infty, \textsf { as } \ x \rightarrow + \infty

From inspection of the graph, we can see that the curve intercepts the x-axis at x = -3, x = 2, x = 3

As the curve touches the x-axis at (-1, 0) then this means that the root x = -1 has multiplicity 2

Therefore,
f(x) = a(x + 1)^2(x + 3)(x -2)( x - 3) where
a is some positive constant.

If we multiply the constants, we can determine the y-intercept:

y-intercept = a x 1² x 3 x -2 x -3 = 18a

Therefore, the y-intercept is at y = 18a

From inspection of the graph, the y-intercept is at y = 4.5

So to determine the value of a: 18a = 4.5 ⇒ a = 1/4

Therefore, the fully factored form of the equation is:


f(x) = \frac14(x + 1)^2(x + 3)(x -2)( x - 3)

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