$\left(3x^3-2x^2-x-5\right)+3\cdot\left(x^2-2x+4\right)$

$\lim_{x\to0}\left|\frac{3x+1}{\sin\left(x\right)}-\frac{1}{x}\right|$

$\left(-\frac{1}{5}a^5+\frac{2}{3}b\right)\left(\frac{2}{3}b+\frac{3}{4}a\right)$

$4x^2+3x+8$

$6x^2<5x+6$

$\cos\left(\pi-x\right)=\cos\left(\pi+x\right)$

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