$\lim_{x\to+\infty}\left(\frac{2x-sin\left(2x\right)}{x+sin\left(2x\right)}\right)$

$16x^2+2x+6$

$-n+3\left(4n+5\right)$

$\left(x-6-y\right)\left(x-6+y\right)$

$6c-\left[-\left(2a+c\right)+-\left(a+c-2a\:-a+\:c\right)+2c\right]$

$\frac{x+3}{3x-2}\le2$

$5,13\:+\:10,5\:-\:12,3\:+12,3+1,9-9$