(adsbygoogle = window.adsbygoogle || []).push({}); 1. The problem statement, all variables and given/known data

ln(3x+5) Determine intervals on which the function is increasing, decreasing, concave up, and concave down.

2. Relevant equations

3. The attempt at a solution

So I did f '(x) = 3/3x+5

this gives me 3x+5 = 0, and I get x = -5/3 (point where the y is zero)

Now, I did f '' (x), and got -3/(3x+5)^2

this gives me (3x+5)(3x+5), i did a number line test, with the only value -5/3, and anything below -5/3 is negative, and before -5/3 is positive

this gives me that, the function is decreasing after -5/3, and increasing after -5/3.

Now what about the concavity?

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# Homework Help: Interval increasing/decreasing

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