$\:x^2-\frac{1}{4}=0$

$f\left(x\right)\:=\:\left(3\:-\:2\:senx\right)^2$

$\int-3xe^{-2x}dx$

$\left(x+5\right)\:\left(x+7\right)$

$\lim\:_{x\to\:\:0}\left(x^{\left(\ln\:\left(x\right)\right)^2}\right)$

$2\sin x=3\cos^2x-2$

$\lim_{x\to\frac{\pi}{2}}\left(\frac{ln\:\left(sin\:x\right)}{\pi-2x^2}\right)$