$\int\frac{x}{\left(x+2\right)\left(2x+1\right)}dx$

$x^22x+50$

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

$6a^2+4ab-9ac-6bc$

$4x^6+2x^5-6x^6+4x+8$

$3\cdot4^2+-10\cdot4+6$

$\frac{x^4}{x^2}+\left(x^2\right)^2;x=3$