$\left(x\:+\:3\:x^3\:sin\left[y\right]\right)\:dt\left[x\right]\:+\:\left(x^4\:cos\left[y\right]\right)\:dt\left[y\right]\:==\:0$

$\frac{x^2-81}{x-9}$

$49^2\cdot343$

$\left(x\:+4\right)\:\left(x+\:3\right)\:\left(x+\:2\right)\:$

$\int_0^{\infty}\left(\frac{36x^4-109x^2+25}{2x+1}\right)dx$

$12c+5\left(5+3c\right)=3\left(9c-4\right)$

$2f+w+f$