$-2cos\left(x\right)-\frac{sin\left(x\right)}{sin^2\left(x\right)}$

$x^2dx+3y\left(5x-4\right)dy=0$

$\lim_{x\to0}\left(\left(\frac{x^2+2x-1}{3x^2}\right)\right)$

$\frac{d}{dx}\ln\left(3x^2-7x+3\right)$

$z^2-5z+6.25$

$4\left(n+3\right)-\left(3+n\right)$

$\frac{d}{dx}\left(3x^5+4y^3=5-3y^5\right)$