$\lim_{x\to0}\left(x+e^{\frac{x}{6}}\right)^{\frac{6}{x}}$

$\lim_{x\to\infty}\left(\sqrt{x+7}-\sqrt{x-7}\right)$

$\int\frac{x^2+4}{x^2\left(x-4\right)}dx$

$\frac{x^2+5x+6}{x^2+2}$

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

$4x-9y-8x+6y$

$\lim_{x\to\infty}\sqrt{9x^2+x}-3x$