$\lim_{x\to\infty}\left(\frac{x^2+2x+2}{e^x}\right)$

$0^2+2\cdot0\cdot3+3^2$

$-2+5x-1y+2x-1$

$\lim_{x\to3}\left(\frac{\sqrt{x^2+7}-4}{\sqrt{x+1}-2}\right)$

$\frac{1+\cos\left(t\right)}{\sin\left(t\right)}-\frac{\sin\left(t\right)}{1+\cos\left(t\right)}=2\cot\left(t\right)$

$\int_{-1}^{\sqrt{3}}\frac{x^{2}}{\sqrt{4-x^{2}}}dx$

$( - 50 ) + x = ( - 30 )$