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The polynomial function is $\"\"$

The maximum real numbers are $\"\"$ ,Since the function $\"\"$ maximum degree is $\"\"$ .

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The function $\"\"$ is sign changes the coeffient of function $\"\"$ ,that has minus number is even for example of real positive zero is $\"\"$ .

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The function $\"\"$ is sign changes the coeffient of function $\"\"$ ,that has minus number is even for example of real negative zeros is $\"\"$ .

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The maximum real numbers are $\"\"$ .