summarize the pertinent information obtained by applying the graphing strategy and sketch the graph of (…

summarize the pertinent information obtained by applying the graphing strategy and sketch the graph of ( f(x)=ln left(x^{2}+36\right) ).\nfind inflection points. select the correct choice below and, if necessary, fill in the answer box to complete your choice.\na. the inflection point(s) is(are) ( x= ) -6,6\n(use a comma to separate answers as needed.)\nb. there are no inflection points.\nchoose the correct graph below.\n
Answer
Explanation:
Step1: Find the first - derivative
Use the chain rule. If (y = \ln(u)) and (u=x^{2}+36), then (y^\prime=\frac{u^\prime}{u}). Since (u^\prime = 2x), (f^\prime(x)=\frac{2x}{x^{2}+36}).
Step2: Find the second - derivative
Use the quotient rule ((\frac{v}{w})^\prime=\frac{v^\prime w - vw^\prime}{w^{2}}), where (v = 2x), (v^\prime=2), (w=x^{2}+36), (w^\prime = 2x). (f^{\prime\prime}(x)=\frac{2(x^{2}+36)-2x(2x)}{(x^{2}+36)^{2}}=\frac{72 - 2x^{2}}{(x^{2}+36)^{2}}).
Step3: Find the inflection points
Set (f^{\prime\prime}(x)=0), then (72-2x^{2}=0). (2x^{2}=72), (x^{2}=36), (x=\pm6).
Answer:
A. The inflection point(s) is(are) (x=-6,6)