$\left(2a+b+c\right)^3$

$-3xyz+\frac{5}{3}mn+\frac{6}{7}xyz-6mn-4xyz$

$\frac{dy}{dx}\left(y=\left(8+7x\right)^{\frac{3}{x}}\right)$

$\lim_{x\to+\infty}\frac{x+x^2\sin\left(\frac{1}{x}\right)}{1+x}$

$\lim_{x\to2}\left(x^2\left(x-2\right)^{\frac{2}{3}}sin\left(x-2\right)^{\frac{1}{3}}ln\left(x-1\right)^3\right)$

$2x+19=6x-9$