$2^4+2^0$

$7x+5x+4x-12;\:x=-12$

$1001-9001-8000$

$\int\sec\left(\frac{x}{2}\right)\tan\left(\frac{x}{2}\right)dx$

$\lim_{x\to0}\frac{3\sin\left(x\right)-x\cos\left(x\right)-2x}{4x^4}$

$\left(x-y\right)dx+\left(2x+\right)dy=0$

$a^5-9a^3+6a^2-20\:-\:-a^4+11a^3-a^2$