$\lim\:_{x\to\:\:1}\left(\frac{\frac{1}{x-1}+\frac{1}{x+1}}{x}\right)$

$x-4.x-4$

$\left(-10\right)^2+\left[-4^2-\left(\sqrt{25}\right)\right]-\left(\sqrt{16+\sqrt[3]{-125}}\right)$

$\frac{1}{n^{2\:}}+\frac{1}{m^2}$

$-43+\left|-37\right|$

$1+2\cos\:\left(x\right)\sin\:\left(x\right)=2\tan\:\left(x\right)\cos\:^2\left(x\right)+1$

$\left(5x+3y-2\right)\left(5x+3y+2\right)$