$\frac{5}{6}\:por\:6\:enteros$

$2a+1b^2$

$\left(a^4-6a^3+8a^2-7a+5\right)\left(-3a^2b^3\right)$

$sen\left(a\right)tan\left(a\right)sec\left(a\right)+1=sec^2\left(a\right)$

$\lim_{x\to0}\left(\frac{sin\left(2x\right)+7x^2+2x}{x^2\left(x+1\right)^2}\right)$

$64b^2-121$

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