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Factor the polynomial function over the complex numbers. f(x)=x^4-x^3-2x−4 Enter your answer in the box. f(x) = The answer is: (x−2)(x+1)(x+i2√)(x−i2√)

User Yellowfog
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1 Answer

1 vote

Answer:

Factors:
(x+i\sqrt2)(x-i\sqrt2)(x+1)(x-2)=0

Explanation:

We are given a polynomial:


f(x)=x^4-x^3-2x-4

We have to factor the given polynomial into its complex factors.

The factorization can be done as follows:


f(x)=x^4-x^3-2x-4 = 0\\x^4-x^3-2x-4 = 0\\x^4-4-x^3-2x=0\\\text{Identity: }a^2-b^2 = (a+b)(a-b)\\(x^4-4)-(x^3+2x) = 0\\(x^2+2)(x^2-2)-x(x^2+2) = 0\\(x^2+2)(x^2-2-x) = 0\\(x^2+2)(x^2-x-2) = 0\\(x^2+2)(x^2-2x-+x-2) = 0\\(x^2+2)((x(x-2)+1(x-2))=0\\(x^2+2)(x+1)(x-2)=0\\\text{Identity: }a^2-b^2 = (a+b)(a-b)\\(x^2-(√(-2))^2)(x+1)(x-2)=0\\(x+i\sqrt2)(x-i\sqrt2)(x+1)(x-2)=0

User Gingemonster
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