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Write a polynomial function in factored and standard form by using third provided information: f(x) is a third degree function; f(0) =12; roots are -2, 2, -3.

User Hariszaman
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Final answer:

The polynomial function in factored form, given the roots and the y-intercept, is f(x) = -(x + 2)(x - 2)(x + 3). The standard form after expanding the factors is f(x) = -x³ - 3x² + 4x + 12.

Step-by-step explanation:

Given that f(x) is a third-degree function that passes through the point (0, 12) and has roots at -2, 2, and -3, we can write the polynomial in its factored form as follows:

f(x) = a(x + 2)(x - 2)(x + 3)

To find the value of a, we use the fact that f(0) = 12.

Substitute x with 0:

12 = a(0 + 2)(0 - 2)(0 + 3)

12 = -12a

a = -1

The factored form of the polynomial is:

f(x) = -(x + 2)(x - 2)(x + 3)

To convert to standard form, expand the factors:

f(x) = -[(x² - 4)(x + 3)]

f(x) = -(x²x + 3x² - 4x - 12)

f(x) = -x³ - 3x² + 4x + 12

The standard form of the polynomial is:

f(x) = -x³ - 3x² + 4x + 12

User Shivam Chawla
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