$2b+5a-b$

$\lim_{x\to1}\left(\frac{1-x}{x^3-2x^2-x+2}\right)$

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

$\frac{2x}{5}-3\frac{5x}{2}\ge\frac{3x}{4}-\frac{2x}{3}$

$9x^2+30x>-25$

$\frac{\left(3x^2+2x\right)}{\left(x^2-3\right)}$

$\frac{d}{dx}\left(\arcsin\left(x+\sqrt{1-x^2}\right)\right)$