$\lim_{x\to3}\left(\frac{2x^2-5x-3}{x-3}\right)$

$100n^2-160n+64$

$\lim_{x\to\infty}\left(\frac{\sin\left(x\right)}{e^x-e^{-x}}\right)$

$\left(\sin\left(x\right)+\cos\left(x\right)\right)\cdot\tan\left(x\right)-\sec\left(x\right)=\sin\left(x\right)-\cos\left(x\right)$

$x^5a+x^5b-a-b$

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

$\frac{1}{2}m^2n+\frac{1}{3}m^2n+\frac{1}{4}m^2n+\frac{1}{6}m^2n$