$x^3\cdot\frac{dy}{dx}+4x^2\cdot y=e^x$

$2x^4-9x^2+5x^2+13x-3\:entre\:x+1$

$p=\left(1-\cos^2\left(x\right)\right)\cot\left(x\right)$

$\int\left(\cos\left(x\right)\cdot\left(\sec\left(x\right)\cdot\tan\left(x\right)\right)\right)dx$

$\lim_{x\to2\pi}\left(\frac{sinx}{x}\right)$

$\frac{dy}{dx}=\frac{2xy}{\left(x^2-1\right)\left(y^2\:+\:2\right)}$

$\left(2x^4-6x^3+4x-4\right)$