$x^2+1-12$

$\cos\left(x\right)-1=-\frac{1}{2}$

$\int\left(\frac{1}{4}\left(cos\left(4x\right)+cos\left(8x\right)^2\right)\right)dx$

$6x+3y-2x+2y$

$\left(2x\tan\left(y\right)+5\right)dx\:+\:\left(x^2\sec^2\left(y\right)\right)dy=0$

$\sen^{2}30^{\circ}+\sec^{2}45^{\circ}$

$x^2-2x+6=2x^2-6x-26$