$x^2-13x+45$

$\frac{9}{7}\left(-\frac{14}{3}\right)\left(-\frac{5}{6}\right)$

$\left(4x^4-3\right)^2$

$\sqrt[4]{x^{12}}.\:\sqrt[3]{x^9}.\:\sqrt{x^6}$

$\lim_{x\to\frac{\pi}{2}}\left(\frac{tanx}{\left(\frac{4}{2x-\pi}\right)}\right)$

$\frac{dy}{dx}=\:2\:sin\left(4x-2y\right)$

$x^2+10x+27\ge0$