$\frac{\sin\left(x\right)}{1-\sec\left(x\right)}\cdot\frac{1+\sec\left(x\right)}{1+\sec\left(x\right)}$

$\frac{\left(1+3sinx\right)dy}{dx}=\frac{1}{y\sqrt{2-y}}$

$\left(7+x\right)\frac{dy}{dx}=4+y$

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

$\sqrt[5]{\frac{3x^{11}y^2}{9x^2}}$

$5.1-2$

$\frac{d}{dx}\left(\frac{x}{x-y}=y^2+3\right)$