$3\cdot21\cdot10^{-3}$

$\tan\left(0.5x\right)+\cos\left(x\right)\tan\left(0.5x\right)$

$\frac{18x^2-9x-8x^4+2}{4x^2+1}$

$9x^2-40x+54=6x^2-22x+27$

$\int\left(6x+1\right)^4\left(2x\right)dx$

$\int\frac{\left(x^2+9\right)^2}{x^2}dx$

$\lim_{x\to1}\left(\frac{ln\left(2-x\right)^2}{x-1}\right)$