$\frac{\left(-9a^4b\right)}{ab^3}$

$16^{30}$

$\int\frac{4x-3}{\left(x+1\right)\left(x-1\right)\left(x+3\right)}dx$

$6^2+6$

$\lim_{x\to\infty}\left(\frac{cos\:\left(x+1\right)}{\:\left(x+1\right)}\right)$

$\frac{1-\sin\left(-x\right)}{\cos\left(x\right)}=\frac{\cos\left(x\right)}{1-\sin\left(x\right)}$

$\left(3x+5\right)\left(5x-25\right)$