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According to Descartes' Rule of Signs, can the polynomial function have exactly 00 positive real zeros? Choose your answer based on the rule only.\newlinef(x)=x5+2x4+8x34x2+5f(x) = x^5 + 2x^4 + 8x^3 - 4x^2 + 5\newlineChoices:\newline(A)yes\newline(B)no

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Q. According to Descartes' Rule of Signs, can the polynomial function have exactly 00 positive real zeros? Choose your answer based on the rule only.\newlinef(x)=x5+2x4+8x34x2+5f(x) = x^5 + 2x^4 + 8x^3 - 4x^2 + 5\newlineChoices:\newline(A)yes\newline(B)no
  1. Count Sign Changes: Count the number of sign changes in the polynomial f(x)=x5+2x4+8x34x2+5f(x) = x^5 + 2x^4 + 8x^3 - 4x^2 + 5. Coefficients: 1,2,8,4,51, 2, 8, -4, 5. Sign changes: 11 (from 88 to 4-4).
  2. Descartes' Rule of Signs: According to Descartes' Rule of Signs, the number of positive real zeros is equal to the number of sign changes or less by an even number.\newlineSince we have 11 sign change, the possible number of positive real zeros is 11 or 12=11-2= -1, which doesn't make sense, so we stick with 11.
  3. Number of Positive Zeros: Since the polynomial can have 11 positive real zero, it cannot have exactly 00 positive real zeros.

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