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N=4; -2, - 1/2 and i are zeros ; f (1) =18

User Sareed
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1 Answer

4 votes

Answer:

f(x) = x^4 + (5/2)x^3 + x^2 + (7/2)x + (5/2)

Explanation:

To find a polynomial function with the given zeros and f(1) = 18, we can start by using the zero-product property to set up the factors of the polynomial.

Given zeros:

-2, -1/2, i

Since i is a complex number, its conjugate, -i, is also a root of the polynomial.

The factors of the polynomial can be written as:

(x + 2)(x + 1/2)(x - i)(x + i)

To find the polynomial, we can multiply these factors together:

(x + 2)(x + 1/2)(x - i)(x + i) =

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

(x^2 + (5/2)x + 1)(x^2 + 1) =

x^4 + (5/2)x^3 + x^2 + (5/2)x + x + (5/2) =

x^4 + (5/2)x^3 + x^2 + (7/2)x + (5/2)

Now we have the polynomial function in standard form:

f(x) = x^4 + (5/2)x^3 + x^2 + (7/2)x + (5/2)

To find f(1), we substitute x = 1 into the polynomial:

f(1) = (1)^4 + (5/2)(1)^3 + (1)^2 + (7/2)(1) + (5/2)

f(1) = 1 + (5/2) + 1 + (7/2) + (5/2)

f(1) = 18

Therefore, the polynomial function that satisfies the given conditions is:

f(x) = x^4 + (5/2)x^3 + x^2 + (7/2)x + (5/2)

User Sean Pearce
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