$2.5xy^{2}-15x^{2}y$

$\frac{d}{dx}\frac{\left(\left(2x+1\right)^2\left(x-6\right)\right)}{\left(\left(x^2+1\right)^3cos\left(x\right)\right)}$

$0.81m^6y^2-\frac{21}{5}m^4y+\frac{49}{9}m^2$

$x-15=15-x$

$\lim\:_{x\to\:0}\left(\frac{\csc\:\left(x\right)}{\csc\:\left(2x\right)}\right)$

$x^5+4x^4-12x^3-34x^2+11x+30$

$\frac{6x}{3}+\frac{2x\:+y}{6}$