let f(x) = ln(x-2)+ln(x-6). Write down the natural domain of f(x).(adsbygoogle = window.adsbygoogle || []).push({});

i got this bit right, it's x>6

find f'(x)

i got 1/(x-2) + 1/(x-6)

which i think is right.

then it says find the intervals for which f'(x) is a. positive and then b. negative.

for a. i put f'(x)>0 and solved for x and i got the right answer, but i'm not sure if this is the right method.

because for b. if i put f'(x)<0 and solve for x i dont get the right answer.

can anyone help???:yuck:

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# Homework Help: Differentiating natural logs

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