# Thread: derivatives with natural logs

1. ## derivatives with natural logs

looking for step by step assistance. any help is greatly appreciated

find the derivative and compute f(1)

$f(x) = ln(x^2 + 3x + 1) ln(x^3 + 1)$

2. Originally Posted by JGaraffa
looking for step by step assistance. any help is greatly appreciated

find the derivative and compute f(1)

$f(x) = ln(x^2 + 3x + 1) ln(x^3 + 1)$
What is your attempt so far?

3. haven't really gotten anywhere with this one, i'm not sure if i should distribute the $ln$ to $(x^2+3x+1)$ and the other $ln$ to $(x^3 +1)$

so confused.

4. 1.use the rule $\left({fg}\right)' = f'g + fg'$
2. you get $(2x+3)/(x^2+3x+1)ln(x^3+1)+3ln(x^2+3x+1)x^2/(x^3+1)$
3. compute f'(x=1).
You'll get $ln(2)+\frac{3}{2} ln(5)$