$2^2-3b+4c-3ab$

$\left(\frac{3}{4}ab-\frac{5}{3}mn+\frac{2}{3}ab+\frac{4}{6}m^2n\right)+\left(-\frac{5}{6}ab-\frac{4}{12}mn+\frac{3}{2}ab+\frac{5}{2}m^2n\right)$

$\frac{dy}{dx}\left(3x^2+3x+4\right)$

$\int\frac{9x^3-3x+1}{\left(x^3-x^2\right)}dx$

$\left\{4x+6\left(y-8\right)+\left[3x-5y-2\left(x+5y\right)\right]\right\}$

$( 2 m ^ { 2 } - x ^ { 4 } ) ^ { 3 }$

$81x^{3\:}+648x^{2\:}-4x-32$