$\frac{d}{dx}\left(\frac{4x+1}{10x-1}\right)$

$\left[\left(-15\right)-\left(-6\right)-\left(23\right)\right]$

$\int\left(\frac{x}{x^2-5x+4}\right)dx$

$\lim_{x\to0}\left(\frac{x^{2}-1}{8^{x}-1}\right)$

$e^{xy}=cosx$

$-2\:+\:\left(-3\right)\:-\:3-\left(-2\right)\left(-3\right)=\:\:\:\:$

$\frac{\left(n+1\right)\cdot\:\left(-3\right)^2}{\left(2n+1\right)\cdot2^n}$