$2\:+3x\:<\:0$

$\int\left(\frac{\cos\left(x\right)}{\left(2\sin\left(x\right)+6\right)^2}\right)dx$

$\lim_{x\to\infty}\frac{\frac{1}{\sqrt{x+h}}-\frac{1}{\sqrt{x}}}{h}$

$\left(x-4\right)\left(x+4\right)-\left(x^2-17\right)$

$349-\frac{6}{x^2}-15x-\frac{15}{x}-6x^2$

$\lim_{x\to\infty}\left(\frac{2}{x^2-3}\right)$

$\frac{2\tan\left(\frac{a}{2}\right)}{1+\tan^{2}\left(\frac{a}{2}\right)}$