$\left(6m^66a\right)$

$\left(x+y^3\right)dx+\left(3y^5+3y^2x\right)dy=0$

$\cos\left(2x\right)\cos\left(x\right)=\cos^3\left(x\right)-\cos\left(x\right)\sin^2\left(x\right)$

$\cos^4\left(x\right)-\sin^4\left(x\right)+1=2$

$\lim_{x\to0}\left(\frac{x^2}{1-12cosx}\right)$

$\frac{dy}{dx}=\frac{\left(5x^2+3x\right)}{y^2}$

$\sqrt{\left(a+b\right)\left(a-b\right)+2ab+2b^2}$