$\frac{dx}{dt}=0.6-\frac{3x\left(t\right)}{500}$

$\left(4\tan\:^2\left(x\right)-1\right)\left(\sin\:\left(x\right)+\cos\:\left(x\right)\right)$

$-\left(n+7\right)-2$

$3x-9>5x+3$

$\left(2^a+6^b\right)^2$

$\int\frac{2x^2-x+6}{\left(x+1\right)\left(x^2+\:2\right)}dx$

$2x+y;\:x=7;\:y=10a$