$\frac{dy}{dx}+3xy-x=0$

$n-2=-2$

$\int\left(\left(2x\right)\cdot sen\left(x^2-4\right)\cdot cos\left(x^2-4\right)\right)\:dx$

$\left(x+y+1\right)e^xdx+\left(e^x+e^y\right)dy=0$

$-\left(12-9\right)\cdot\left(8-18\right)$

$\int\frac{1}{\left(x+1\right)\left(n-x\right)}dx$

$1\:\frac{\left(9-4\right)}{5}$