$8-z+3.$

$\lim_{x\to0.001}\frac{1-\cos\left(0.001\right)}{0.001}$

$\left(\frac{\left(x^2-9\right)}{x^2+5x-6}\right)\left(\frac{\left(x^2+x-2\right)}{x^2+4x-21}\right)$

$\frac{d}{dx}\left(\frac{x\left(x^2+2\right)^{\frac{1}{2}}}{\left(x+1\right)^{\frac{4}{3}}}\right)$

$8-3x\ge5$

$4x^{8}\cdot5x^{5}$

$\frac{dy}{dx}=\frac{1}{2}x+1$