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Use the given zero to find the remaining zeros of each function.

Thank you!! :)

Use the given zero to find the remaining zeros of each function. Thank you!! :)-example-1
User Aracelis
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1 Answer

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10 votes

Answer:

remaining zeros: {-1/2, √3}

Explanation:

Given the polynomial function f(x) = 2x³ +x² -6x -3 has one zero at x = -√3, you want the remaining zeros.

Conjugate zeros

A polynomial with rational real coefficients and zeros that are roots or complex numbers will have all such roots in conjugate pairs.

The root that is the conjugate of -√3 is +√3.

Product of roots

The product of the roots of an odd-degree polynomial will be the opposite of the ratio of the constant to the leading coefficient. Here, that means the product of roots is ...

-(-3/2) = 3/2

We already know that two of the three roots are ±√3, so their product is -3. The remaining root will be ...

(3/2)/(-3) = -1/2

The remaining zeros of f(x) are √3 and -1/2.

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Additional comment

When the degree of the polynomial is even, the constant term will be the product of the roots. This odd/negative, even/positive behavior comes from the fact that each zero (q) corresponds to a factor (x -q).

The product of these binomial factor constants is the constant in the standard-form polynomial. It will have a negative sign if there are an odd number of factors.

Use the given zero to find the remaining zeros of each function. Thank you!! :)-example-1
User Entalyan
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