$\lim_{x\to7}\left(\frac{98-7x-\left|x^2-14x\right|}{\left|x^2-196\right|-147}\right)$

$2sen\left(x\right)cos\left(2x\right)-2cos\left(x\right)sen\left(2x\right)$

$x\frac{dy}{dx}=y+xy$

$-1487,3-876$

$\lim_{x\to\infty}\left(\frac{4x}{lnx}\right)$

$3x^2-2x+1\:.\:x-2$

$1+5+5+12+5+5$