Let's start by analyzing the polynomial function given by:
\[ f(x) = - (x - 4)(x^2 - 4) \]
Part 1: Degree and Leading Coefficient
First, we need to expand the polynomial to find its degree and leading coefficient.
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Expand \( f(x) \): \[ f(x) = - (x - 4)(x^2 - 4) \] Distributing \( (x - 4) \): \[ = -[(x \cdot (x^2 - 4)) - (4 \cdot (x^2 - 4))] \] \[ = -[x^3 - 4x - 4x^2 + 16] \] The expansion gives: \[ f(x) = -x^3 + 4x^2 + 16x - 16 \]
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From the polynomial \( f(x) = -x^3 + 4x^2 + 16x - 16 \), we can identify:
- The degree is 3 (the highest exponent).
- The leading coefficient is -1 (the coefficient of the \( x^3 \) term).
Thus,
(a) The degree of the polynomial is 3 and the leading coefficient is -1.
Part 2: End Behavior
The leading coefficient is negative, and the degree is odd (3), which affects the end behavior:
- As \( x \to \infty \) (the right end), \( f(x) \to -\infty \).
- As \( x \to -\infty \) (the left end), \( f(x) \to \infty \).
Therefore, the description of the end behavior is:
The curve opens down because the leading coefficient is negative. Because the polynomial is cubic, the graph has end behaviors in opposite directions, hence the other end opens up to the left.
(b) The curve opens down to the right because the leading coefficient is negative. Because the polynomial is cubic, the graph has end behaviors in the opposite direction, so the other end opens up to the left.
Part 3: Graph of the Function
Based on the characteristics of the polynomial we identified:
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The function will have the following end behavior:
- Left side goes up (as \( x \to -\infty \)).
- Right side goes down (as \( x \to \infty \)).
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A cubic polynomial typically has inflection points and may have up to two local extrema.
Among the provided options, we need to look for a graph that shows:
- An upward trend as you move to the left.
- A downward trend as you move to the right.
Considering the provided graphs:
- Option C portrays a downward trend towards the right and an upward trend towards the left, which aligns with the end behaviors described above.
Thus, the correct graph of the function \( f(x) \) is most likely C.