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According to the Fundamental Theorem of Algebra, which polynomial function has exactly 8 roots?f(X) 3x4 +2xfox)- (6x -4x5-10 3x2-4

According to the Fundamental Theorem of Algebra, which polynomial function has exactly-example-1
User Mcjudd
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2 Answers

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The number of roots of a polynomial is determined by the highest power of the variable after all simplifications has been done. For the first option, after the brackets has been expanded, the highest power of x will be 8. The second option will have the highest power of x as 16. The third option will have the highest power of x as 6 while the last option will have the highest power of x as 10. Therefore, the polynomial function with exactly 8 roots is f(x) = (3x^2 - 4x - 5)(2x^6 - 5).
User Vroomfundel
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1 vote
Answer:
A. (3x²-4x-5)(2x⁶-5)

Step-by-step explanation:
The fundamental theorem of Algebra states that:
"A polynomial of degree 'n' will have exactly 'n' number of roots"

We know that the degree of the polynomial is given by the highest power of the polynomial.
Applying the above theorem on the given question, we can deduce that the polynomial that has exactly 8 roots is the polynomial of the 8th degree

Now, let's check the choices:
A. (3x²-4x-5)(2x⁶-5)
The term with the highest power will be (3x²)(2x⁶) = 6x⁸
Therefore, the polynomial is of 8th degree which means it has exactly 8 roots. This option is correct.

B. (3x⁴+2x)⁴
The term with the highest power will be (3x⁴)⁴ = 81x¹⁶
Therefore, the polynomial is of 16th degree which means it has exactly 16 roots. This option is incorrect.

C. (4x²-7)³
The term with the highest power will be (4x²)³ = 64x⁶
Therefore, the polynomial is of 6th degree which means that it has exactly 6 roots. This option is incorrect

D. (6x⁸-4x⁵-1)(3x²-4)
The term with the highest power will be (6x⁸)(3x²) = 18x¹⁰
Therefore, the polynomial is of 10th degree which means that it has exactly 10 roots. This option is incorrect

Hope this helps :)
User Nate Flink
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