$\frac{cot\left(t\right)+tan\left(t\right)}{sec\left(t\right)}$

$t^{3}\frac{dx}{dt}=x^{3}-x^{3}t^{2}$

$\lim_{x\to\infty}\left(\frac{e^x}{6}\right)$

$x^2+21x-232\:cuando\:x=3$

$\lim_{x\to0}\left(\frac{x^2+\sin\left(x^2\right)}{\arctanh\left(x^2\right)}\right)$

$\frac{0.9\left(1.6\right)}{9}$

$\lim_{x\to1}\left(\frac{3\left(x^2\right)-13x-10}{2\left(x^2\right)-7x-15}\right)$