$\left(2n^2xnx4\right)^2$

$\frac{d}{dx}-\frac{x}{6y}$

$\lim_{x\to\infty}\left(\frac{3x}{\sqrt{9x^2+1}}\right)$

$\frac{d^2}{dx^2}\left(10+50\sqrt{t}\right)$

$\sqrt{12h}^4$

$4x^2+5+25$

$\lim_{x\to-infinity}\:\frac{\left(\left(6\left(2^x\right)\right)-\left(5\left(2^{-x}\right)\right)\right)}{\left(7+\left(8\left(2^x\right)\right)\right)}$