$8\:+\:14\:-\:\left(-15\right)\:-\:2\:+\:\left(-6\right)\:-\:10$

$2a^2-4ab-5a+10b$

$\lim_{x\to\infty}\left(\frac{\left(x\right)^x}{\left(x+1\right)^x}\right)$

$\left(2a-3b-4c\right)\left(5a+6b\right)$

$xsiny^2+x^2ycosy^2\frac{dy}{dx}=0$

$\sec\left(x\right).\cos\left(x\right).\tan\left(x\right)=1-\cos^2x$

$\int\frac{1}{\sqrt{9x^2+16}}dx$