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Let 
f(x)=(-x)/(ln^(2)(x-1)).
Select the correct description of the one-sided limits of 
f at 
x=2.
Choose 1 answer:
(A)

{:[lim_(x rarr2^(+))f(x)=+oo" and "],[lim_(x rarr2^(-))f(x)=+oo]:}
(B)

{:[lim_(x rarr2^(+))f(x)=+oo" and "],[lim_(x rarr2^(-))f(x)=-oo]:}
(C)

{:[lim_(x rarr2^(+))f(x)=-oo" and "],[lim_(x rarr2^(-))f(x)=+oo]:}
(D)

{:[lim_(x rarr2^(+))f(x)=-oo" and "],[lim_(x rarr2^(-))f(x)=-oo]:}

Let f(x)=xln2(x1) f(x)=\frac{-x}{\ln ^{2}(x-1)} .\newlineSelect the correct description of the one-sided limits of f f at x=2 x=2 .\newlineChoose 11 answer:\newline(A)\newlinelimx2+f(x)=+ and limx2f(x)=+ \begin{array}{l} \lim _{x \rightarrow 2^{+}} f(x)=+\infty \text { and } \\ \lim _{x \rightarrow 2^{-}} f(x)=+\infty \end{array} \newline(B)\newlinelimx2+f(x)=+ and limx2f(x)= \begin{array}{l} \lim _{x \rightarrow 2^{+}} f(x)=+\infty \text { and } \\ \lim _{x \rightarrow 2^{-}} f(x)=-\infty \end{array} \newline(C)\newlinelimx2+f(x)= and limx2f(x)=+ \begin{array}{l} \lim _{x \rightarrow 2^{+}} f(x)=-\infty \text { and } \\ \lim _{x \rightarrow 2^{-}} f(x)=+\infty \end{array} \newline(D)\newlinelimx2+f(x)= and limx2f(x)= \begin{array}{l} \lim _{x \rightarrow 2^{+}} f(x)=-\infty \text { and } \\ \lim _{x \rightarrow 2^{-}} f(x)=-\infty \end{array}

Full solution

Q. Let f(x)=xln2(x1) f(x)=\frac{-x}{\ln ^{2}(x-1)} .\newlineSelect the correct description of the one-sided limits of f f at x=2 x=2 .\newlineChoose 11 answer:\newline(A)\newlinelimx2+f(x)=+ and limx2f(x)=+ \begin{array}{l} \lim _{x \rightarrow 2^{+}} f(x)=+\infty \text { and } \\ \lim _{x \rightarrow 2^{-}} f(x)=+\infty \end{array} \newline(B)\newlinelimx2+f(x)=+ and limx2f(x)= \begin{array}{l} \lim _{x \rightarrow 2^{+}} f(x)=+\infty \text { and } \\ \lim _{x \rightarrow 2^{-}} f(x)=-\infty \end{array} \newline(C)\newlinelimx2+f(x)= and limx2f(x)=+ \begin{array}{l} \lim _{x \rightarrow 2^{+}} f(x)=-\infty \text { and } \\ \lim _{x \rightarrow 2^{-}} f(x)=+\infty \end{array} \newline(D)\newlinelimx2+f(x)= and limx2f(x)= \begin{array}{l} \lim _{x \rightarrow 2^{+}} f(x)=-\infty \text { and } \\ \lim _{x \rightarrow 2^{-}} f(x)=-\infty \end{array}
  1. Analyze Right Approach: Analyze the behavior of the function as xx approaches 22 from the right (x2+x \to 2^+).\newlineAs xx approaches 22 from the right, the numerator x-x approaches 2-2. The denominator ln2(x1)\ln^2(x-1) approaches ln2(1)\ln^2(1), which is 00. Since the denominator approaches 00 and the numerator approaches a negative value, the function 2211 approaches negative infinity.
  2. Analyze Left Approach: Analyze the behavior of the function as xx approaches 22 from the left (x2x \to 2^-).\newlineAs xx approaches 22 from the left, the numerator x-x still approaches 2-2. However, we must consider the behavior of the natural logarithm function ln(x1)\ln(x-1) as xx approaches 22 from the left. The natural logarithm of a number close to 2200 from the left is negative, and as xx approaches 22, ln(x1)\ln(x-1) approaches 2244 which is 2255. Since the denominator is the square of ln(x1)\ln(x-1), it will be a small positive number. Therefore, the function 2277 approaches negative infinity as well.
  3. Choose Correct Answer: Choose the correct answer based on the analysis.\newlineFrom Step 11 and Step 22, we have determined that both one-sided limits as xx approaches 22 lead to negative infinity. Therefore, the correct answer is:\newline(D) {limx2+f(x)= and limx2f(x)=}\left\{\lim_{x \to 2^{+}}f(x)=-\infty \text{ and } \lim_{x \to 2^{-}}f(x)=-\infty\right\}

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