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According to Descartes' Rule of Signs, can the polynomial function have exactly 11 positive real zero, including any repeated zeros? Choose your answer based on the rule only.\newlinef(x)=x4+5x3+2x24x5f(x) = x^4 + 5x^3 + 2x^2 - 4x - 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 11 positive real zero, including any repeated zeros? Choose your answer based on the rule only.\newlinef(x)=x4+5x3+2x24x5f(x) = x^4 + 5x^3 + 2x^2 - 4x - 5\newlineChoices:\newline(A)yes\newline(B)no
  1. Count Sign Changes: Count the number of sign changes in the coefficients of f(x)=x4+5x3+2x24x5f(x) = x^4 + 5x^3 + 2x^2 - 4x - 5. Coefficients: 1,5,2,4,51, 5, 2, -4, -5. Sign changes: 11 (from 22 to 4-4).
  2. Descartes' Rule: 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, f(x)f(x) can have either 11 or 00 positive real zeros.
  3. Determine Positive Zero: Determine if f(x)f(x) can have exactly 11 positive real zero.\newlineSince the possible number of positive real zeros is 11 or 00, it is possible for f(x)f(x) to have exactly 11 positive real zero.

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