$\lim\:_{\theta\:\to\:\frac{\pi\:}{2}}\left(\frac{1-\sin\:\left(\theta\:\right)}{\cos\:\left(\theta\:\right)}\right)$

$\frac{t^3s^3}{y^3}-x^3$

$ln\:\left(\frac{\left(x\sin\left(x\right)\right)}{\left(\sqrt{\sec\left(x\right)}\right)}\right)$

$\frac{dy}{dx}=2\cos5x$

$in\left(t^2\left(3t^2+6\right)\right)$

$6\cdot4x-8+20$

$4^{-5}\cdot4^5$