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According to the Fundamental Theorem of Algebra, how many roots exist for the polynomial function? (9x + 7)(4x + 1)(3x + 4) = 0 1 root 3 roots 4 roots 9 roots

2 Answers

3 votes

Answer:

answer is b

Explanation:

User Nik Klassen
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1 vote
3 roots, since the polynomial is of third degree.

This follows immediately from the zero product property: if
ab=0, then either
a=0 or
b=0. We have


<span>(9x + 7)(4x + 1)(3x + 4) = 0

from which it follows that


\begin{cases}9x+7=0\\4x+1=0\\3x+4=0\end{cases}

each of which admits only one solution.

Or, using the fundamental theorem of algebra, expanding we have a polynomial that is of third degree:


</span>(9x + 7)(4x + 1)(3x + 4)=108 x^3 + 255 x^2 + 169 x + 28

The theorem states that a polynomial
a_nx^n+\cdots+a_1x+a_0 will have up to
n distinct roots. In this case, it follows that there are exactly 3, since the solutions to the system above are all distinct.
User Daniel W Strimpel
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8.5k points