Answer:
1 or 3
1, only
Explanation:
To find the positive real roots, all we look at the coefficients and the number of times the sign changes. The coefficients are -4, -3, 2, -4, 1. As we can see, the sign changes 3 times meaning that 1 and 3 are the positive real roots.
To find the negative real roots, substitute -x into x and see how many numbers are negative; -4, 3, 2, 4, 1. As we can see there is 1 negative number meaning there is only 1 negative real root.
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