To determine the end behavior of the function \( f(x) = 6(x - 9)(x^2 + 9) \), we need to analyze the leading term as \( x \) approaches positive and negative infinity.
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Identify the degree of the polynomial:
- The term \( x - 9 \) is a linear term, and \( x^2 + 9 \) is a quadratic term.
- The degree of \( (x - 9) \) is 1, and the degree of \( (x^2 + 9) \) is 2. Therefore, the overall degree of the polynomial is \( 1 + 2 = 3 \).
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Leading coefficient:
- The leading term (when fully expanded) will be \( 6x^3 \) since the leading term from \( (x - 9) \) is \( x \) and from \( (x^2 + 9) \) is \( x^2 \). Therefore, we multiply the leading coefficients: \( 6 \times 1 \times 1 = 6 \).
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End behavior analysis:
- Since the degree is odd (3) and the leading coefficient is positive (6), the end behavior will be:
- As \( x \to +\infty \), \( f(x) \to +\infty \)
- As \( x \to -\infty \), \( f(x) \to -\infty \)
- Since the degree is odd (3) and the leading coefficient is positive (6), the end behavior will be:
Thus, the end behavior is "Up on the right side and down on the left side."
The correct answer is: D. Up on the right side, down on the left side.