$3-a+b+2b-2c+3a+2c-3b$

$\int\frac{x}{1+\sqrt{1-x}}dx$

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

$\lim_{x\to\frac{3.1416}{2}}\:\:\:\left(\frac{1-senx}{cosx}\right)\left(0\right)$

$3x-y=-11$

$4x^{-2}-15^{-1}=0$

$\left(8-6+4\right)+\left(8-4+3\right)$