$\lim\:_{x\to\:0}\left(\frac{\sqrt{2x}}{-1+sen\left(2x+1\right)}\right)$

$a^2-2a^3+3a^4-4a^5+6a^6$

$8\tan^2x-24=0$

$55x^2y^2+15xy$

$\frac{dy}{dx}=\frac{18}{x}$

$\int\frac{4x-2}{\left(x-1\right)^2}dx$

$-20\cdot6\cdot\left(-14\right)\cdot\left(-7\right)\cdot\left(-2\right)$