$f\left(x\right)=2x^2+4$

$\lim_{x\to\infty}\left(\frac{sin\left(\frac{4}{x}\right)}{\arctan\left(\frac{1}{x}\right)}\right)$

$2x+2-5\left(x-3\right)\ge-8$

$14d-9+21w-7dw+2$

$\lim_{x\to0}\left(\sqrt{1+\frac{2}{x}}-\sqrt{1+\frac{3}{x}}\right)$

$\lim_{x\to\pi}\:\cot\left(x\right)$

$\log\left(x^2-3\right)-\log\left(x\right)=\log\left(\frac{x^2-3}{x}\right)$