$12k=108$

$\left(y-9\right)\left(y+5\right)$

$\frac{2}{\left(1+\cos\left(x\right)\right)\cdot\sin\left(x\right)}=\frac{2}{\sin\left(x\right)}$

$\int\left(x^4\right)\left(\ln\left(x\right)\right)^2dx$

$y=2ln\:x$

$\lim_{x\to0}\left(\frac{\sqrt[n]{1+x}-1}{x}\right)$

$\frac{5}{9}ab^3-2a^3b-1b^3a+8a^3b$