$\frac{1}{\cos\:\left(\frac{3\pi\:}{2}-\arccos\:\left(\frac{-2}{3}\right)+\arctan\:\left(\frac{1}{7}\right)\right)}$

$\lim_{x\to-1.9}\left(\frac{x^2-4}{x+2}\right)$

$117.04-89.04$

$220+45-6+20$

$\int3t\sqrt{t-3\:}dt$

$x\left(x\:-12\right)>\left(x-4\right)^2$

$\left(-25\right)-\left(-3\right)$