$\frac{d}{dx}\left(\frac{1+\sin\left(x\right)}{x\cdot\cos\left(x\right)}\right)$

$y'=\left(15x^2+4\right)\left(6y+5\right)$

$\left(-3x^2+6\right)^3$

$\int\frac{sen^3\left(x\right)}{cos^2\left(x\right)+cos^4\left(x\right)}dx$

$\frac{y^2-5+y^3+y}{y^2+3-5}$

$\left(23-y\right)^2$

$\int\frac{\left(5x+2\right)}{x^2-4}dx$