$\frac{1}{\cos\left(x\right)}-\frac{\cos\left(x\right)}{1+\sin^2\left(x\right)}$

$12a^2\:-\:28a\:-\:5$

$\left(a^0\right)^2\cdot a$

$\frac{d}{dx}\left(x^3+y^3=4xy+1\right)$

$\left(\sqrt[3]{2-1}\right)\left(-2\right)$

$\int\left(5x^3e^{-3x}\right)dx$

$\left(x^3-\frac{5}{2}\right)^2$