$\left(2x^3-6x^2+3x+9\right):\left(x+3\right)$

$\sqrt{a}\cdot\sqrt{a}$

$\frac{dy}{dx}\sqrt[4]{\frac{x}{3x+1}}$

$\lim_{x\to\frac{\pi}{2}}\left(\frac{\cot\left(x\right)-\cos\left(x\right)}{\cos\left(x\right)}\right)$

$\left(4m+6\right)\left(4m-9\right)$

$\lim_{t\to1}\left(\frac{t^2+3t\:+2}{t^2-t-2}\right)$

$\frac{\cos\left(x\right)^2}{\sin\left(x\right)^2}+\cos\left(x\right)\sec\left(x\right)$