The function p(x)= x+1 x^ 2 -5x+1 has a denominator whose real zeros are irrational.

MATHEMATICS · Multi-part · AP · AP Precalculus · Polynomial and Rational Functions · Polynomial and Rational Functions

Problem

The function p(x)=x+1x2−5x+1p(x)=\frac{x+1}{x^{2}-5x+1} has a denominator whose real zeros are irrational. (a) Solve x2−5x+1=0x^{2}-5x+1=0 and provide decimal approximations of the roots correct to three decimal places. (b) For each root found in part (a), calculate the corresponding left–hand and right–hand limits of p(x)p(x) as xx approaches that root. Clearly indicate whether the function approaches +∞+\infty or −∞-\infty on each side. (c) Summarize your findings by constructing a sign chart for p(x)p(x) on the real line, labeling each interval with the sign of p(x)p(x) and marking all vertical asymptotes.

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