$4.9x^2-15x+0$

$\int_x^0\left(2\cdot t\right)dt$

$\frac{\left(x+2\right)\left(x-2\right)+10x+8}{\left(x+2\right)x+4}$

$123+456$

$\int\sqrt{\cot x}\csc^2x\:dx$

$x^2+6x+9-\:\left(x+2\right)^2+\left(x+4\right)^2-\:\left(x+5\right)^2$

$\frac { 3 x ^ { 3 } } { x + 1 } - x - 11$