$-2u^2dx+2x\cdot u\cdot du-udx$

$\frac{-18x^3y^2}{6x^2y}$

$\left(4a^{x+1}+1\right)\left(4a^{x+1}-1\right)$

$\sqrt{2a}.\sqrt{2x}$

$\lim_{x\to\frac{\pi}{4}}\left(\frac{\cos\left(x\right)+\sin\left(2x\right)\cos\left(x\right)}{\cos\left(x\right)^2}\right)$

$4n^2+2n-6=0$

$\left(\sin\left(a\right)-\cos\left(a\right)\right)^2$