$\left(m^2-n^2-mn\right)\cdot\left(2m+4n+1\right)$

$\int\left(\frac{1}{x\left(x^2-1\right)^{\frac{3}{2}}}\right)dx$

$\left(x+y\right)^2y'=25$

$\left(6x-7\right)\left(-6x-7\right)$

$2sen7xcosx-sen6x$

$\frac{\sin^2x-\cos^2x}{1-\cos^2x}=\sec\left(x\right)^2-2$

$y'=y-x$