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3 What is/are the z-intercepts of the graph y=-2³-52² - 3x + 9? OA (-3,0), (-1,0) O. B. (3.0), (1,0) OC. (3.0), (-1,0) O.D. (-3,0), (1,0) Reset Selection m

3 What is/are the z-intercepts of the graph y=-2³-52² - 3x + 9? OA (-3,0), (-1,0) O-example-1
User Gvgvgvijayan
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1 Answer

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19 votes

We will have the following:

We will determine the x-intercepts as follows:


f(x)=-x^3-5x^2-3x+9

Thus, the critical points will be given by:


\begin{gathered} f^(\prime)(x)=-3x^2-10x-3=0\Rightarrow x=(-(-10)\pm√((-10)^2-4(-3)(-3)))/(2(-3)) \\ \\ \Rightarrow x=-3 \\ \\ and \\ \\ \Rightarrow x=1 \end{gathered}

Now, we have that the x-intercepts are located at:


\begin{gathered} (-3,0) \\ \\ and \\ \\ (1,0) \end{gathered}

User NatNgs
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