$6x^3-4x^2+3x-12+\left(-5x+9x^2\right)-\left(4x^3-9x+13\right)$

$\int\frac{x^3-2x+4}{x^5-13x^3+36x}dx$

$\int\left(\frac{5x^2}{x-1}\right)dx$

$\left(m^2+n\right)+\left(-m^2-2n\right)$

$2^{-3}+2^3$

$\int\frac{x^3-3x^2+x-1}{x^2}dx$

$\frac{sen30\:+\:cos60\:+\:tg45\:+\:csc30\:+\:3}{sen37\:+\:sen53}$