$2\sin\left(15\right)\cos\left(15\right)$

$\frac{dy}{dx}\left(\pi y\sqrt{y^2+x^2}\right)$

$\left(3x+1\right)^2\:-\:5x^2\:+2x\le\left(2x-1\right)^2-36$

$\frac{2s}{s-1}+\frac{1}{s}$

$\left(3x-2y\right)\frac{dy}{dx}=x$

$\lim_{x\to0}\left(x^2\cdot\ln\left(x^2\right)\right)$

$-4+\left(-3\right)\cdot\left(5-\:\left(-2\right)\right)\left(-13\right)-19$