$\left(x^2y^3-\frac{1}{1+9x^2}\right)dx+x^3y^2dy=0$

$\int\tan\left(x\right)\left(-10\cos\left(x\right)-3\sec\left(x\right)\right)dx$

$\int\frac{1}{\left(x^2\right)\left(x^2-4\right)^2}dx$

$xdy+ydx=3dx$

$2\tan^2x=2-\sec^2x$

$\frac{-150}{-25}$

$\int_{\frac{\pi}{4}}^{\frac{\pi}{2}}\sec xdx$