$\lim_{n\to\infty}\left(\sqrt{\frac{2n}{n+7}}\right)$

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

$\lim_{x\to\frac{5\pi}{2}}\left(\frac{1}{-csc^2\left(\frac{x}{5}\right)}\right)$

$\left(2y+2z\right)\left(2y-2z\right)$

$6b\:-\:3b\:+\:8a\:-\:18b\:+\:a\:$

$-\left(+2\right)+\left(-4\right)-\left(+3\right)-\left(-3\right)+\left(-7\right)$

$\left(a^5-7b^4\right)^2$