Refer to the polynomial function h(x) = -3x^2(5x +5)(x-1) that you wrote in Question 1 of Finding the Zeros of a Polynomial Function. Describe and provide an explanation for the end behavior of h(x)

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To analyze the end behavior of the polynomial function \( h(x) = -3x^2(5x + 5)(x - 1) \), we need to consider both its degree and the leading coefficient.

  1. Identify the degree:

    • The term \( -3x^2 \) has a degree of 2.
    • The term \( (5x + 5) \) is linear (degree 1).
    • The term \( (x - 1) \) is also linear (degree 1).
    • Therefore, the total degree of \( h(x) \) is: \[ 2 + 1 + 1 = 4 \]
  2. Identify the leading coefficient:

    • The leading term of \( h(x) \) can be determined by multiplying the coefficients of the highest degree terms:
      • The leading term from \( -3x^2 \) is \( -3x^2 \).
      • The leading term from \( 5x + 5 \) is \( 5x \).
      • The leading term from \( x - 1 \) is \( x \).
    • When we multiply these together considering the leading degree: \[ \text{Leading term} = -3 \cdot 5 \cdot 1 \cdot x^2 \cdot x \cdot x = -15x^4 \]
    • Thus, the leading coefficient of the polynomial is \( -15 \) and the leading degree is \( 4 \).
  3. Analyze the end behavior:

    • For a polynomial of even degree (which \( 4 \) is) and a negative leading coefficient (which \( -15 \) is), the end behavior can be described as follows:
      • As \( x \to \infty \) (x goes to positive infinity), \( h(x) \to -\infty \) (the function goes down).
      • As \( x \to -\infty \) (x goes to negative infinity), \( h(x) \to -\infty \) (the function also goes down).

Therefore, the end behavior of the polynomial function \( h(x) = -3x^2(5x + 5)(x - 1) \) is that both ends of the graph (as \( x \) approaches \( \infty \) and \( -\infty \)) go down towards negative infinity, resulting in a graph that opens downwards.