I have a problem with these sequences: $\displaystyle \lim_{x\to\infty} \frac{ln(3n^2+20n+5)}{ln(n^9-3n+12)}$

$\displaystyle \lim_{x\to\infty} n ln(n^{2}+1)-2n(lnn)(lnn)^{1/n}$

$\displaystyle \lim_{x\to\infty}\frac{1*4*7*...*(3n+1)}{2*5*8*... *(3n+2)} $

The first one - I don't know how to get rid of the ln(something) function or maybe I'm just doing it in a wrong way. The second one - everything would be great if there wasn't this $\displaystyle ln(n)[ln(n)]^{1/n}$ which I don't know what to do with. The third one - I don't have any idea about this one... I would appreciate your hints or solutions. I've been trying to solve them for so long but I constantly get wrong answers (I used wolfram alpha).