$\lim_{x\to1}\left(\frac{\left(2x-1\right)^2-1}{2x-2}\right)$

$\int\frac{5x+18}{\left(x+4\right)\left(x+3\right)}dx$

$\frac { t - x } { x }$

$-y+3+7-7$

$2\left(2w-3\right)-5\left(2v-3\right)$

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

$\lim_{x\to0}\left(15xe^{\frac{1}{x}}\right)$