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What is the polynomial function of lowest degree with lead coefficient 1 and roots i, –2, and 2?

User Pavel Lint
by
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2 Answers

4 votes

Answer:b.f(x) = x^4 – 3x^2 – 4

Explanation:

User Ruslan Bes
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4.0k points
8 votes

Answer:

x^4 - 3x^2 - 4.

Explanation:

Imaginary roots occur as conjugate pairs so a 4th roots is -i.

So in factor form we have:

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

= (x^2 + 1)(x - 2)(x + 2)

= (x^2 + 1)(x^2 - 4)

= x^4 - 3x^2 - 4.

User Lars Koudal
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4.1k points