$\frac{2a}{31}+\frac{6}{14}$

$\lim_{x\to\infty}\:\left(x^{2x}\right)$

$\lim_{x\to1}\left(ln\left(\frac{x^9-1}{x^5-1}\right)\right)$

$\int\tan^5\left(2x\right)\sec^{-2}\left(2x\right)dx$

$\int_{-1}^19t\:e^{3t}dt$

$227=88-y$

$\frac{cos^2\theta-2\:sin^2\theta}{1-3\:sin^2\theta}$