$\frac{sin\left(2\left(x-6\right)\right)}{sin\left(x-6\right)}=2cos\left(x-6\right)$

$\lim_{x\to0}\left(1+\frac{x}{n}\right)^{3n}$

$\int\left(7\cos\left(\frac{x}{3}\right)\right)dx$

$\int_2^4\left(\frac{1}{1+\left(x+3\right)^2}\right)dx$

$-x^2-y^2$

$y^2\left(x+2y\right)$

$\lim_{x\to-\infty}\left(\frac{ln\left(x^2+x^4\right)}{ln\left(x^5+x^6\right)}\right)$