$\frac{dx}{dt}+\frac{3}{500}x=0,\:6$

$\frac{8^2y^3-10x^3y}{2x^2y}$

$\lim_{x\to\frac{1}{2}}\left(\frac{ln\left(2x\right)}{2x-1}\right)$

$ycost+2te^y+\left(sent+t^2e^y+2\right)y'=0$

$\frac{1}{2}\left(x+4\right)=\frac{1}{3}x$

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

$54\cdot2$