$\lim_{x\to5}\left(\frac{2x^2-50}{2x^2+3x-35}\right)$

$-\left[-2+1-\left(-1+\left(-1\right)+2\right)-1\right]$

$\frac{3x^2+6}{x^3+x^2-2x}$

$-2\left|3\right|\left|-3\right|$

$\frac{dy}{dx}\left(y=\left(x^5+5\right)^2\left(\sqrt{2x^2+3}\right)\right)$

$\frac{\sec^2x-\sin^2x}{\tan^2x}$

$4-108x^2$