$3e^x\tan ydx+\left(1-e^x\right)\sec ydy=0$

$\int x\left(\pi^2-1\right)dx$

$0.45\left(6000\right)$

$\int_{180}^{240}\left(x\cdot\left(\frac{1}{1800}\right)\left(240-x\right)\right)dx$

$\lim_{x\to0}\left(x^{ln\left(2-e^x\right)}\right)$

$x^2+2x-7$

$dy=-\left(y-1\right)^2dx$