I think You should break it down to the First and third One because of
The answer is: [D]: " 2.6 " .
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Given: a = - 2.6 ; What is the value of "-a "?
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So, what is the value of " - (-2.6)" ?
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The opposite of a negative is a positive;
so, " - (-2.6) = 2.6 " ; which is: "Answer choice: [D] " .
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Answer:

Step-by-step explanation:
Given that f(x) is a polynomial function.
This implies that f(x) has x terms of positive integral degrees and also rational coefficients only.
Since an irrational root is given a root of f(x), we find that its conjugate also should be a root of f(x)
i.e. If
is a root, then
is also a root.
(Because this only when multiplied will make coefficients rational)
So the factors of f(x) should be atleast

There can be other factors also but this is compulsory