$4a^2-6a^2+8a+19a^4$

$3u\:x\:2w^9\:x\:8u^{8\:}x\:w^4$

$\frac{d}{dx}\left(11x^4atan\left(6x\right)\right)$

$\left(1-\cos^2\left(a\right)\right)-\left(1-\sin^2\left(a\right)\right)$

$\left(6-4x-x^2\right)^2$

$\frac{d^2}{dx^2}\left(f^3\left(x\right)\right)$

$9r\:+\:5q\:-\:2r$